Auto Login
Each user can determine if he wants to enable the auto login feature in Open WebMail. When enabled, the user don't have type his username and password in every login to Open WebMail. Open WebMail will do this automatically for him. However, for security reason, the auto login feature will be actived only if user doesn't log out in previous session and the previous session is still not timeouted. Further more, the sysadm can limit the range of IPs that are allowed to use the auto login feature.
Multiple Languages/Multiple Charsets
Open WebMail is currently available for more than 30 languages, and it is quite easy to add new language to Open WebMail if yours is still not supported. For languages with more than one charsets, Open WebMail will choose one as the default charset for the language. If a message is written with charset other than the default, it will be converted to the default charset automatically.
Strong MIME Message Capability
Open WebMail has very well support for MIME messages. While most webmail packages present MIME messages poorly compared to traditional POP clients, Open Webmail presents MIME messages in an attractive format comparable to that presented by Microsoft Outlook. Either inline or uuencoded attachments are supported.
In addition to the presention, Open WebMail also allow user to compose complex HTML messages with inline attachments or external attachments. A friendly WYSIWYG editor HTMLArea 3.0 has been built into Open WebMail, the user can write HTML messages conformtably and easily without any knowledge of HTML tags. This HTML editor can be used on IE5.5+ for Windows or Mozilla1.3+ for all platforms :)
Full Content Search
Full content search with regular expression support is provided. When a user enters a keyword in the search box, the scope of the mail folder is limited to the keyword related messages. This means the user can use the sort or static functions on the search result. The scope limit is released when the user selects another folder or refreshes the current folder.
Draft Folder Support
This feature enables the user to write a message in a number of stages, even over several days. The user can save an unfinished message into the draft folder and continue editing at any time.
Confirm Reading Support
The user can request a 'confirm-reading receipt' for each message sent. When the message is read by the recipient, a receipt will be sent back to this user.
SpellCheck Support
The spelling check in Open WebMail is very user-friendly and powerful: It makes suggestions for mis-spelled words, and the user can correct the errors very easily by selecting one of the suggestions from a drop-down menu.
POP3 Support
Multiple POP3 accounts can be defined, allowing a single user to fetch mails from a number of mail servers. All messages fetched will be stored in the INBOX folder. Should the fetch operation exceed 10 seconds (due to a slow link or large message for example), the operation will be put into background to avoid an http timeout.
Mail Filter Support
Multiple filter rules can be set to move or copy incoming mails to different folders automatically or even delete them directly. The user can categorize mails from a specific person or spammer, and identify mails containing viruses very easily by defining rules of sender, receiver, SMTP relay, subject, body or filename of attachments.
In addition to the static filter rules, openwebmail has build-in five smart filters: repeatness filter, bad format from filter, faked smtp filter, faked from filter and faked exe contenttype filter. Repeatness filter, bad format from filter and faked SMTP filter are useful in filtering messages from spammer, faked from filter and faked exe contenttype filter are useful in filtering messages generated from virus.
Since mail filtering is activated only in Open WebMail, messages will stay in the INBOX until the user reads their mail with Open WebMail. 'finger' or other mail status check utilities may report new mail incorrectly, since they are not aware of filters: A command tool 'openwebmail-tool.pl' is provided for use as finger replacement, which performs mail filtering before reporting mail status.
AntiSpam Support through SpamAssassin
Open WebMail can use the SpamAssassin as the external spamcheck module to scan messages fetched from pop3 servers or all incoming messages. The SpamAssassin will determine a spamlevel for each scanned message based on its content. The user can define a spamlevel threshold for all his messages in Open WebMail, any message with spamlevel more than this threshold will be moved from INBOX to the SPAM folder automatically.
Open WebMail also supports the Spam/NotSpam Learning through the sa-learn program in SpamAssassin. In case the spamlevel determined by SpamAssassin is not very appropriate, the user can train the system by telling it to learn the messages as Spam or NotSpam.
AntiVirus Support through ClamAV
Open WebMail can use the ClamAV as the external viruscheck module to scan messages fetched from pop3 servers or all incoming messages. If a message or its attachments is found to have virus, Open WebMail will move the message from INBOX to the VIRUS folder automatically.
Calendar with Reminder/Notification Support
The user can keep track of their appointments, meetings, birthdays, whatever, with the build-in calendar in Open WebMail. This calendar provides several views, including year view, month view, week view and day view, so the user can browse their scheduled events very easily. There is also reminder support for scheduled events, user can specify the days that the reminder should look ahead and the first 5 upcoming events will be displayed in the top of mail folder view. If the user want the event reminder to be available outside the webmail system, he can also specify a notification email address, eg: the one used by mobile phone, for each scheduled event, so he can get notification of these events on his mobile phone.
Webdisk Support
The webdisk module provides a web interface for user to use his home directory as a virtual disk on the web. It is also designed as a storage of the mail attachments, the user can freely copy attachments between mail messages and the webdisk.
The / of the virtual disk is mapped to the user's home directory, any item displayed in the virtual disk is actually located under the user home directory.
Webdisk supports basic file operations, eg: mkdir, rmdir, copy, move, rm, file upload and download. Download of multiple files or directories is supported, webdisk compresses the files into a zip stream on the fly in the transmission. It also handle many types of archives, including zip, arj, rar, tar.gz, tar.bz, tar.bz2, tgz, tbz, gz, z.... The user can compress, decompress or list the contents of archives without copying them into his computer.
HTTP Compression
Open WebMail supports compression of HTML content over HTTP. With compression turned on, the average page size has been reduced for over 80%. This feature effectively reduces the use of nework bandwidth between the client computer and the webmail server and is very useful for users with slow connection to the webmail server, eg: dialup users, PDA users.
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