What is Claws Mail?

Claws Mail is an email client aiming at being fast, easy-to-use and powerful. It is mostly desktop-independent, but tries to integrate with your desktop as best as possible. The Claws Mail developers try hard to keep it lightweight, so that it should be usable on low-end computers without much memory or CPU power.

What Claws Mail is not

Claws Mail is not a full-featured Personal Information Manager like Evolution or Outlook, although external plugins provide these functionalities. Claws Mail will not let you write and send HTML emails or other kind of annoyances, hence it may not be the software you need in some business environments.

Main features

Claws Mail sports almost everything a perfect email client needs. Mail retrieval over POP3, IMAP4, local mbox, over SSL; support for various authentication schemes. It has multiple accounts and mailboxes, powerful filtering and search functionality, import/export capabilities using a number of formats, support for GnuPG (digital signatures and encryption). It supports plugins, customisable toolbars, spell checking, a number of guards to prevent any data loss, per-folder preferences, and much more. A list of features can be found at www.claws-mail.org/features.php.

History of Claws Mail

Claws Mail has existed since April 2001. It was initially named Sylpheed-Claws and changed its name to Claws Mail in November 2006. The primary goal of Sylpheed-Claws was to be a test-bed for potential features of Sylpheed, so that new features could be tested thoroughly without compromising Sylpheed's stability. Sylpheed-Claws developers regularly synchronised their codebase with Sylpheed's codebase, and Sylpheed's author, Hiroyuki Yamamoto, took back the new features he liked once they were stabilised.

Originally both Sylpheed and Claws Mail were based on GTK1. The work on the GTK2 versions started in early 2003, and the first modern (GTK2-based) Sylpheed-Claws was released in March 2005. Since about this time, Sylpheed and Sylpheed-Claws' goals started to diverge more, and Sylpheed-Claws became an entity of its own. This is why its name is now Claws Mail.

Useful URLs

Website: www.claws-mail.org

Latest News: www.claws-mail.org/news.php

Plugins: www.claws-mail.org/plugins.php

Icon Themes: www.claws-mail.org/themes.php

Tools: www.claws-mail.org/tools.php

Mailing Lists: www.claws-mail.org/MLs.php

Bugtracker: www.thewildbeast.co.uk/claws-mail/bugzilla/

Source code:

The initial wizard

The first time that you start Claws Mail, you will be asked a few questions in order to set up an account. These questions are easy to answer and grouped in several short pages.

First you will be asked to fill in your name, (usually guessed from the operating system), your email address, and the name of your organisation, (optional).

The following page will allow you to enter details of how to retrieve your mail. The format of the page will be determined by the "Server type":

POP3

If you choose POP3, you will need to enter the server address, username, and password. The password is optional, if you don't provide it here then you will be prompted for it each time it is needed.

IMAP

If you choose IMAP, you will need to enter the server address, username, password, and IMAP server directory. The password is optional, if you don't provide it here then you will be prompted for it each time it is needed. The IMAP server directory is also optional, often it is not needed and can be left empty.

Local mbox file

If you choose Local mbox file, you will need to enter the location of your local mailbox spool file. This location depends on your Operating System, but values like /var/mail/username or /var/spool/mail/username are common, where username is your system login.

When you click the "Auto-configure" button, Claws Mail will attempt to configure your account's servers based on your email address and the type of account you have chosen.

On the next page you will enter the address of your SMTP server, (sometimes referred to as "Outgoing server"). You will also be asked whether to authenticate when sending mail; this is often not the case if you're using an ISP to connect to Internet, and often the case if you are configuring a professional account.

If you chose either POP3 or Local mbox file, the next page will ask you where you want to save your mail on disk. The default, "Mail", is usually ok and will save your mails in a directory called Mail in your home directory.

If Claws Mail is built with support for OpenSSL, you will next see the "Security" page, here you will be able to choose to use SSL encryption to send and receive your emails. Most ISPs do not enable this, but many companies do; if you're unsure about it, you can leave them unselected.

You can now click on the Save button, and start enjoying Claws Mail.

Getting mail

Retrieving your email can be done from the toolbar button named "Get mail" or from the "Receive" submenu of the "Message" menu.

If you want Claws Mail to check your mail automatically at regular intervals, you can ask it to do so from the "Mail handling: Receiving" preference page which you'll find in the "Configuration/Preferences..." menu. Just click the "Automatically check new mail every [...] minute(s)" checkbox, and set the interval to your liking.

Reading your mail

Once you have retrieved your emails, the Inbox folder will contain them. The total number of emails in a folder is shown at the right of the folder's name, along with the number of unread and new emails in it. To see them, click on the folder row in the folder list, and the list of emails in that folder will be displayed in the Message List pane. You can then select an email using the mouse, or by using the Up and Down keys to navigate through the list, and the Space bar to display and scroll emails. You can use other keys to navigate through emails, like P and N (previous and next).

Writing your first mail

When clicking on the "Compose" button of the toolbar, a composition window will open. This window contains different fields which you should be able to recognise easily: if you have multiple accounts, the From field can be used to select which account you want to use for this email; the To field is for recipient of the email. When you fill it in, a second To field will appear, so that you can send the email to multiple recipients. You can also change the To field to a Cc field or other types of fields, by using its dropdown menu, or by typing in the field that you require. After that, you will be able to set the subject of your email, then type its body.

A little note about an email's subject: Claws Mail will ask you for confirmation if you attempt to send an email with an empty subject. This is because it can be annoying for the recipient to receive emails without a subject, as it doesn't help in handling email.

Sending your first mail

When you have finished writing your first email, you can either click the "Send" button to send your email immediately, or use the "Send later" button to queue the message for later sending. When using "Send", the composition window will close itself when the mail has been sent; it will stay open if there is an error. When using "Send later", the composition window will immediately close, and your email will be stored in your Queue folder. It will then be sent when you click the "Send" button in the main window's toolbar.

The emails that you send are saved in the Sent folder of your mailbox, so that you can recall what you wrote to whom, or use an already sent email as a template to write another.

Mail folders

If you receive a lot of emails, you will probably soon find that your Inbox folder is growing to the point where you have a hard time finding an email again, even if you received it just a few days ago. This is why Claws Mail, like most good mail clients, provides you with multiple possibilities in organising your mails.

You can create as many folders and subfolders as you need. For example, one folder for your family, one folder for friends, folders for mailing-lists, archive folders for old mails that you still want to have available, etc. To create a new folder, simply right-click on its parent folder and choose "New folder..." from the drop-down menu. If you want to create a folder "Friends" inside your Inbox folder, for example, just right-click on the Inbox folder, choose "New folder...", and type in "Friends" in the dialogue that appears. Click the OK button, and the new folder is created.

Folder organisation

Now that you have created folders, you can manipulate them and their contents using menu items or drag 'n' drop. Moving one folder into another, for example, can be done by right-clicking on the folder you want to move, choosing the "Move folder..." menu item, and selecting the destination folder. This will move the folder, with the mail it contains, to a subfolder of the chosen folder. Alternatively, you can drag a folder to another one by clicking on it, keeping the mouse pressed, moving the mouse cursor over the destination folder and releasing the button.

If you want to remove a folder and the mail it contains, simply right-click on the folder and choose "Delete folder...". As this is potentially harmful, (the mails in the folder will be deleted and not recoverable), you will be asked for confirmation.

In the same manner that you move a folder to another one, you can move emails from one folder to another. The same method applies for this: either drag 'n' drop emails to a folder, or choose "Move..." after right-clicking on the mail. You can select multiple emails by using the Control or Shift key while clicking on them. You can also copy emails to another folder by pressing the Control key when drag'n'dropping, or by choosing "Copy..." from the email's contextual menu.

IMAP subscriptions

The IMAP protocol allows one to store a list of subscribed folders. Most mail user agents hide the unsubscribed folders away from the GUI, and have a little window allowing to subscribe to these unsubscribed folders. In Claws Mail, subscriptions are respected by default, and only subscribed folders will be displayed. If you want to see all your folders, you can just uncheck "Show subscribed folders only" in the IMAP mailbox' contextual menu or the account preferences. You'll be able to subscribe and unsubscribe folders from this contextual menu too. If the unsubscribed folders are hidden from the list, you will have two ways to subscribe to a folder: either show all folders, subscribe the ones you want, and hide unsubscribed folders again; or, if you know the folder's name, use "Create new folder" in its parent's contextual menu.

Filtering

Once you have a nice folder hierarchy in place, you'll probably want Claws Mail to sort your incoming emails automatically, in order to avoid having to move messages manually each time they arrive. For this you can use the Filtering feature.

You will find the filtering preferences via the "Configuration" menu, "Filtering" item. From this dialogue you will be able to define new rules, modify or delete existing rules, re-order the rules, and enable/disable them. Filtering rules are defined by five things: the enabled status, a name, an account name, a condition, and an action. All disabled rules are simply ignored. The "Name" entry is optional, it's there to help you identify your rules. An account name can be chosen, which will restrict the rule to mail retrieved from the named account only, skipping it for mail retrieved from all other accounts. The default value is "All", which means that the rule is global and will be applied to all mail, regardless of the account from which it was retrieved, (see paragraph below). The condition format is an expression defining what Claws Mail should look for when filtering mail, for example: "to matchcase claws-mail-users" is for messages sent to any address containing "claws-mail-users". You can easily define conditions by clicking the "Define..." button at the right of the field. The last part of a filtering rule is the action, which instructs Claws Mail what to do with mail matching the condition we just defined. For example, "mark_as_read" marks the mail as read as soon as it arrives in your inbox, or "move #mh/Mailbox/inbox/Friends" moves the mail to your "Friends" subfolder. Here, too, a "Define..." button is available to help you define the action to take.

Filtering rules can be assigned to a single, specific account. To do this select an account from the "Account" combo below the "Name" entry. When you set a specific account the filtering rule will only be applied to messages retrieved from the named account. The default value is "All", which means that the rule will be applied globally, to messages retrieved from any account. When filtering messages manually, if there are any per-account filtering rules defined, you will be asked what you wish to do with those rules. Possible choices are to skip the rules, or apply these rules regardless of the account to which they belong, or use the rules for the currently selected account. Caution: if you unset the "Show this message next time" checkbox and click "Filter", on subsequent manual filtering this choice will be applied without any confirmation. Account specific rules are only available for filtering, (at incorporation or manually), the feature is not available for folder Processing or Pre/Post-Processing.

Once you have defined the rule, you can add it to the list of rules with the "Add" button. Don't forget that the order of the rules is important: if Claws Mail finds a rule suitable for an email that either moves or deletes the email, it will stop looking for further rules for that email. This is why, at the right of the rules list, you will find four buttons allowing the re-ordering of rules. The rules can also be reordered by drag 'n' drop.

There is also a quick method of creating filtering rules based on the selected message. After selecting a mail of the type you want to filter, choose "Create filter rule..." from the "Tools" menu, and choose a type from the submenu: "Automatically" mainly helps for mailing-lists posts, "by From" creates a filter based on the sender of the email, "by To" creates a filter based on the recipient, and "by Subject" creates a filter based on the subject. Each one of these types of filtering has its advantages, it's up to you to find out what would be the more practical. Usually, "by From" is nice to sort out your regular contacts' mails, whereas "by To" is more useful to sort mails sent to your different accounts.

Searching

There are several methods for searching your emails.

One of them is relatively standard, and can be found in the "Edit" menu, it's the "Search folder..." item. This will open a window where you can specify one or more fields to search in: From, To, Subject, and Body. After having specified your criteria, click on the "Back" or "Forward" buttons to navigate through the matching emails, or use "Find all" to select all the matching emails at once. Be aware that searching for text in the body of emails is much slower than searching in its headers, because the body of emails isn't cached by Claws Mail. "Extended Search" mode can be turned on by clicking the relevant checkbox, thus allowing you to use match expressions like those used in "Filtering" rules.

If you're looking at a large email and want to find a particular part of it, you can use the "Find in current message..." item of the "Edit" menu. This works like search in a text document.

The final way of searching for emails is using "Quick Search", which you can display or hide by clicking the little magnifying glass icon under the Message List. It is also accessible from the "Quick Search" item of the "Edit" menu. "Quick Search" is more powerful than the normal search as it can search in standard headers (From, To, Subject) or in "Extended" mode using just about any criteria you can think of. When in "Extended" mode, the "Information" button is visible, enabling you to see the search syntax. An "Edit" button is also available which allows you to quickly create a rule. You can also configure "Quick Search" to search recursively through subfolders, whether it should reset itself when you change folders, and whether to use Type-ahead search (this is a search which results update dynamically if you pause in the typing).

When you hit Enter after having specified the search string, the Message List will shrink to present you with only the matching messages. If you set the search to be recursive, any subfolder of the current one that has matching emails will change its icon to a magnifying glass icon. This way, you can search in your whole mailbox at once. If the search is in Sticky mode, the filter will stay applied when you go to another folder. This can be disturbing at first, as you can forget about it, but is useful in some cases, for example if you want to search in the body of emails and are not sure of which folder contains the searched email: a recursive search on the body of emails in a whole mailbox can be really slow.

Basic preferences

The first tab of the account preferences, "Basic", contains, as its name indicates, basic account data. In this tab you can specify your name, email address, organization and basic connection information. The name of the account is just the name Claws Mail will use when referring to this account, for example, in the account switcher at the lower right-hand corner of the main window. The server information lets you specify the receiving protocol to use (which is not modifiable for existing accounts), the server(s) used to receive or send your emails (usually pop.isp.com and smtp.isp.com) and your login on the receiving server.

In the "Receive" tab you are able to change the default behaviour of Claws Mail. For example, leaving messages on the server for a while, preventing downloading of mails that are too large, or specifying whether you want the filtering rules to apply to this account's mails. The "Receive size limit" is used to limit the time spent downloading large emails. Whenever you receive a mail larger than this limit, it will be partially downloaded and you will later have the choice to either download it entirely or delete it from the server. This choice will be presented to you while viewing the email.

The "Send" tab contains preferences for special headers that you might want to add to your outgoing emails, like X-Face or Face headers, and authentication information for sending emails. Most of the time, your ISP allows its subscribers to send email via the SMTP server without authenticating, but in some setups, you have to identify yourself before sending. There are different possibilities for doing that. The best one, when available, is SMTP AUTH. When not available, you'll usually use POP-before-SMTP, which connects to the POP server, (which is authenticated), disconnects, and sends the mail.

The "Compose" tab holds options for changing the behaviour of the Composition window when used with the account. You can specify a signature to insert automatically, and set default Cc, Bcc or Reply-To addresses.

In the "Privacy" tab you can choose the default level of paranoia for your account. You might want all outgoing emails to be digitally signed and/or encrypted. Signing all outgoing emails, not only important ones, will for example allow you to protect yourself from faked mails sent on your behalf to coworkers. This can help solve embarrassing situations.

The "SSL" tab is also security related, although this time its settings apply to the transport of your emails and not their content. Basically, using SSL encrypts the connection between you and the server, which prevents people from snooping on your connection and being able to read your mails and your password. SSL should be used if it is available.

Finally, the "Advanced" tab allows you to specify ports and domains if the defaults are not used. Normally you can leave these empty. You can also specify folders for sent, queued, draft, and deleted messages here.

Account types

We saw earlier that once an account is created, you can't change its type (protocol) anymore. This is because preferences for these different types are not quite the same, most of the POP3 related options are irrelevant for IMAP, for example.

Multiple accounts

You can easily create multiple accounts in Claws Mail. For POP accounts, you can choose to store all email from your different accounts in the same folder(s), using the Receive tab preference. IMAP and News accounts each get their own mailbox in the folder tree.

You can choose which accounts get checked for new mail when using the "Get All" command (or "Get Mail" in the toolbar) by checking the relevant box in the Receive tab of their preferences or in the "G" column of your accounts list.

More filtering

By default filtering rules are global, but they can also be assigned to a specific account. When fetching mail, any rules that are assigned to a specific account will only be applied to mails that are retrieved from that account.

Mail from any account can be filtered into another account's folders, for example, a mail received by POP3 could be filtered into an IMAP account's folder, and vice-versa. This is either a useful feature or an annoying one, depending on what you want to achieve. If you'd rather avoid that, but still want to automatically sort your incoming mail, the best thing to do is to disable Filtering on certain accounts, and use Processing rules in the Inbox folders that you specified, as Processing rules are automatically applied when entering a folder and can be manually applied from a folder's context menu.

Basic management

The address book is accessible via the "Tools/Address book" menu. It is arranged in different sections: the "Address Book" and its subsections, which contain the contacts that you added locally; the vCard sections, which contain imported vCards; and, if support for them was built into Claws Mail, the LDAP and jPilot sections, containing contacts from your LDAP servers or handheld devices.

In the "Address Book" section, you can create multiple address books; each one is able to contain addresses and/or folders. This can help you in organising your contacts by category. In addition to this, you can create groups of addresses, which can be used from the composition window to send mails to multiple people at once. The menus in the address book window allow you to do all of this. For example, you can create a Family folder inside your "Personal Addresses" address book, using the "Book/New folder" menu when "Personal Addresses" is selected, or by right-clicking on it. In the same way, you can add contacts to an address book or folder by using the "Address" menu, or by right-clicking an item in the list in the right-hand part of the window. When adding a contact, a new window will appear, where you'll be able to specify the details of the contact in the first tab (Display Name, First Name, ...), and a list of email addresses in the second tab.

A simpler way to save your contacts to your address book is to save them when reading one of their emails, using the "Tools/Add sender to address book" menu, or by right-clicking on an email address in the message view.

Exporting and importing addresses

Claws Mail can import address books easily from the majority of email programs. From the "Tools" menu in the address book, you will be able to import Pine or Mutt address books. As these formats are not so widespread, you can also import LDIF files. LDIF is a widely-used format, so most other email programs can export their address book to this format. Importing an LDIF file is done via "Tools/Import LDIF file" and is a three-step operation: select the file to import and an address book name, check the fields you want to import if the defaults do not please you, then use the "Save" button.

Filtering messages using the address book

It is possible to filter messages by matching addresses found in headers against the address book, use for this the match type "Found in addressbook" when defining the condition expression of a filtering rule. You have to select the address header to match against a part of the address book. The address header can be To, From, Cc, Reply-to and Sender (if at least one address in that header matches, the rule will be applied). Some special items allow to match at least one address found in "Any" address header, or to match "All" addresses found in all address headers. Click the "Select..." button to choose the address book part to search in (either a book or a sub-folder), or select "Any" to search in the whole address book.

Advanced features

Actions

Actions allow you to use all the power of the Unix command-line with your emails. You can define various commands, taking parameters such as the current email file, a list of emails, the currently selected text, and so on. In this way, you'll be able to perform various tasks such as editing a raw mail in your text editor, hide what you mean using ROT-13, apply patches contained in emails directly, and so on. The only limit is your imagination. You can create and configure Actions via the "/Configuration/Actions..." menu.

The "Tools/Actions/" menu will contain one submenu item for each action that you have created. When you have selected one or more messages in the Message List, or are viewing a message in the Message View, selecting one of these menu items will invoke the action, and, depending on how it was defined, will pass the message(s) to it.

Additionally, it is possible to add toolbar entries for your actions. To do so, open the "Configuration/Preferences" menu and select "Toolbars/Main Window". Select "User Action" in the "Item type" dropdown menu, then select the Action in the "Event executed on click" dropdown menu, and click the "Icon" button to select the icon that you want to use.

Example 1. Simple "Open With..."

Menu name: Open with/kate Command Line: kate %p

Opens the file of the selected decoded MIME part (%p) with the kate text editor.

Example 2. Spam management using Bogofilter

Menu name: Bogofilter/Mark as Ham Command Line: bogofilter -n -v -B "%f"

Marks the currently selected mails (%f) as "not spam" using Bogofilter.

Menu name: Bogofilter/Mark as Spam Command Line: bogofilter -s -v -B "%f"

Marks the currently selected mails (%f) as "spam" using Bogofilter.

Example 3. Search DuckDuckGo using an external script

Menu name: Search/DuckDuckGo Command Line: |/path/to/ddg_search.pl

Searches DuckDuckGo for the currently selected text (|) using the external script ddg_search.pl.

Templates

Templates are used in composition windows, and act as a model for emails. Templates can be filled with static text and dynamic parts, such as the original sender's name ("Dear %N, ..."), the date, etc. When applying a template, the dynamic fields will be replaced with the relevant values. You can configure templates via the "Tools" menu.

When applying a template, you will be asked to "Insert" or "Replace", the difference between replacing and inserting is only concerned with the message body. "Replace" will replace the current composition window message body with the body defined in the template, clearing it if the template body is empty. "Insert" will insert the template's body, if set, at the current cursor position.

Whether you choose to Insert or Replace, any To, Cc or Bcc field that is defined in the template will be appended to the compose window's recipients list. If it is defined, the template's Subject will always replace the compose window's Subject.

Symbols can be used in all parts of the templates and will be substituted with their respective dynamic value if possible, otherwise no value will be used. This often makes more sense if you apply a template when replying or forwarding, otherwise most of the symbols value will be undefined. There is no restriction on which symbols can be used in template parts, even if inserting the body (%M or %Q) may make no sense in common situations.

When applying a template, the body is processed first, then the To, Cc, Bcc and Subject fields follow.

Further information and examples of usage can be found in the user-contributed FAQ on the Claws Mail website www.claws-mail.org/faq/.

Processing

Processing rules are the same as Filtering rules, except that they are applied when entering a folder or when manually applied from a folder's context menu and apply only to this folder. You can use them to automatically move old mails into an archive folder, or for further dispatching of emails, and more. You can set each folder's Processing rules by right-clicking on it.

Processing rules are accompanied by Pre-processing and Post-processing rules. Like Processing rules, they apply when opening a folder or manually applying them from a folder's context menu, but like Filtering rules, they are shared across all folders. You can configure them from the "Tools" menu. Pre-processing rules are executed before the folder's specific Processing rules, while Post-processing rules are executed afterwards.

Colour Labels

Colour labels can be used to denote a message as having a particular significance. To set a colour label simply right-click a message in the Message List and use the "Color label" submenu.

Colour labels are user-configurable. Both the colour and the label can be set by the user. Preferences can be found on the "Configuration/Preferences/Display/Colors" page.

Tags

Tags are short text notes which may be set on messages. They are useful for classifying messages with your own words. These tags can be used later to find the mails with Quick Search or to manage them with filtering or processing rules, for example.

Tagged messages are displayed with a yellow background at the top of the Message View. This line shows all tags associated with the message. You can enable the "Tags" column in the Message List, so tagged items can be seen without having to open the message.

Setting of tags is done by right-clicking on the message in the Message List or by the corresponding option in Message menu. A panel with the existing tags is shown and you can select some of them or just add a new one. Removal of existing tags is also allowed, of course.

Once tags exist it's even easier, as the context menu allows you to set and unset tags with just one click to the selected messages. Mixed selections of tagged and untagged messages are allowed, and Claws Mail is clever enough to do what you want to do in any case.

Mailing-List support

Claws Mail offers mailing-list support from the "Message/Mailing-List/" submenu. When you have a mailing-list message selected, the submenu allows you to quickly initiate subscribing, unsubscribing, posting, getting help, contacting the list owner, and viewing the list archive; either by opening a new Compose window with the appropriate address pre-filled, or by opening the URL in your web browser.

Plugins

Plugins are the mechanism for extending Claws Mail' capabilities. For example, imagine that you want to store your mails in a remote SQL database. In most mailers out there this is simply impossible without reworking the internals of the mailer. With Claws Mail you can simply write a plugin to achieve the task.

This is just an example of the possibilities. A good number of plugins developed for Claws Mail already exist, and more are to come. The Extending Claws Mail section gives details of them.

Deploying Claws Mail

The initial configuration wizard tries to guess various fields using information gathered from the system, such as username, hostname, and more. As it is oriented towards general use, the default values often have to be fixed. However, this wizard is customisable, in a manner designed to allow system administrators to deploy Claws Mail easily over various users of one machine, or even over multiple machines installed via some replication tool.

The first part consists of creating a wizard configuration template and setting the various default parameters of a new Claws Mail installation.

• Start with a user who does not have a ~/.claws-mail directory, ideally a new user.

• Start Claws Mail and go through the wizard. The values you fill in will be of no use for the future deployment, so you can click next-next-next.

• Once the wizard is finished and you have Claws Mail' main window opened, configure the various defaults you want to have in the master. You can load plugins, add people or LDAP servers in the addressbook, create filtering rules, and so on.

• If needed, and if the deployed Claws Mail will use MH folders, you can create subdirectories in the mailbox.

• Next, quit Claws Mail.

• Now, edit the newly created wizard template file, ~/.claws-mail/accountrc.tmpl. In this file, you will see different variables, corresponding to the wizard's fields. You can leave some commented, in which case the usual default will be used, or specify values or variables. Not all fields can contain variables; for example, smtpauth, smtpssl and recvssl are booleans, either 0 or 1, and recvtype is an integer value. The other fields, like name, email, or recvuser, are parsed by the wizard and the variables they contain are replaced by values. This allows you to specify everything as needed for your site, even if you have strange server names or server logins.

• Save this file, and delete both ~/.claws-mail/accountrc, (which contains your dummy account) and ~/.claws-mail/folderlist.xml, (so that the folder tree will be correctly parsed for new users). Recursively copy .claws-mail to /etc/skel/; if the deployed Claws Mail will use MH folders, also copy the created Mail directory. chown all of /etc/skel/.claws-mail and /etc/skel/Mail to root:root for security reasons.

• Test! Create a new user, login as that user, run Claws Mail. If you filled everything as you wanted, this user will just have to fill in his passwords.

• Now, if you're creating a master for a site-wide deployment, you can continue with this process. If you were just doing it for one machine, you're done!

Here are the different variables of the accountrc.tmpl file:

Here are the different variables you can use in the domain, name, email, organization, smtpserver, smtpuser, smtppass, recvserver, recvuser, recvpass, imapdir, mboxfile and mailbox fields:

Be sure not to use a variable before defining it.

Hidden preferences

There are a number of hidden preferences in Claws Mail, preferences that some users who we wanted to please couldn't live without, but which did not have a place in the GUI in our opinion. You can find the following, and change them while Claws Mail is not running, in ~/.claws-mail/clawsrc.

There's a small tool written in Perl-GTK called Clawsker which provides a user-friendly GUI for tweaking these settings instead of direct editing of clawsrc. You can read more about it on the Clawsker page.

Autofaces

Claws Mail allows setting the Face and X-Face headers directly from files, either globally for all defined accounts or on a per-account basis. These files must be placed in the ~/.claws-mail/autofaces/ directory.

If they exist, the global Face and/or X-Face headers for all accounts are taken from the face and/or xface files respectively. In a similar manner, Face and/or X-Face headers for a specific account can be provided by face.accountname and/or xface.accountname, where accountname is the name of the account you want this header to be associated with.

If the name of the account contains characters which may be unsuitable for the underlying filesystem (including spaces) these are replaced by underscores ("_") when searching for the autofaces of that account. For example, if your account is called "<My Mail>", the name for the X-Face filename for that account would be ~/.claws-mail/autofaces/xface._My_Mail_. Be aware that this feature doesn't check the content of the files, or for duplication of headers, (most mailers, including Claws Mail, will ignore duplicates and display the last one only).

Plugins

Claws Mail's capabilities are extended by plugins, which are listed below.

Plugins are installed in $PREFIX/lib/claws-mail/plugins/ and have a suffix of ".so". To load a plugin go to "Configuration/Plugins" and click the "Load Plugin" button. Select the plugin that you want and click the "Open" button.

If you don't find the plugin you're looking for, it is possible that your Operating System distribution provides it in a separate package. In this case, search for the plugin in your package manager.

Some plugins provide the same functionality as others, (for example, the 3 anti-Spam plugins). In this case you will have to choose which one to load, as Claws Mail will refuse to load more than one of the same type.

There is a list of all plugins available at www.claws-mail.org/plugins.php.

If you're a developer, writing a plugin to extend Claws Mail's capabilities is probably the best and easiest solution. We will provide hosting to your code, and will be glad to answer your questions in the mailing-list or on the IRC channel, #claws on Libera.chat.

Network access from the plugins

Some of the external plugins, for example RSSyl, vCalendar, Libravatar or Fancy, need Internet access for their operations (retrieving feeds in the case of RSSyl or vCalendar, and fetching images in the case of Libravatar or Fancy). These plugins use the Curl library. Hence, if your Internet access is restricted by a proxy, you will need to tell libCurl to use this proxy. This is done by setting an environment variable, http_proxy. For example, http_proxy=http://user:passwd@myproxy.example.com:8080 will tell libCurl to connect to port 8080 of the machine myproxy.example.com, with the user "user" and password "passwd" to connect to the Internet.

You can either set this variable before starting Claws Mail by using, for example, http_proxy=http://user:passwd@myproxy.example.com:8080 claws-mail, or you can set it in your ~/.bashrc file (or your shell equivalent), by adding the following line[1]: export http_proxy=http://user:passwd@myproxy.example.com:8080 (you'll have to reconnect to have it taken into account).

Plugin path configuration

By default, when loading a plugin, its full path is saved in ~/.claws-mail/clawsrc.

As most users have only one copy of Claws Mail installed and always use the same installation method, this is not a problem.

However, if you have multiple copies of Claws Mail installed and want to share the same configuration among them, this may not work, particularly when using different versions of Claws Mail.

A second installed copy will try to load the plugins installed by the first and, if the versions differ, the plugins will be rejected.

In order to avoid this problem you can manually edit the plugins section in the clawsrc file, replacing the full path with just the plugin file name of those you want to load relative to the copy of Claws Mail being run.

In so doing, each copy of Claws Mail will try to load those plugins from its own plugin directory, rather than a fixed location.