![[big logo]](images/exim-blue-ld.png)
Exim is a message transfer agent (MTA) developed at the University of Cambridge for use on Unix systems connected to the Internet. It is freely available under the terms of the GNU General Public Licence. In style it is similar to Smail 3, but its facilities are more general. There is a great deal of flexibility in the way mail can be routed, and there are extensive facilities for checking incoming mail. Exim can be installed in place of sendmail, although the configuration of exim is quite different to that of sendmail.
The current version of Exim is 4.43. See the Download page to get a copy. There were a number of issues with earlier 4.3x versions so their use is discouraged. Security fixes in this release mean that all previous versions should be obsoleted in favour of 4.34 or 4.41. Users of 4.40 should be aware that there is an issue which may cause the exim daemon to die - this is fixed in 4.41 and later.
Exim 3 and previous versions are now considered obsolete. Exim 3 is not being developed any further, nor is it being actively maintained, though if a really serious bug were found, it would be looked at.
The old system filter has been deleted from the site - it is not appropriate for current mail configurations. If you are still using it please discontinue immediately - it creates severe collateral spam issues.
The Exim/Mailman HOWTO for Mailman 2.1 with Exim 4 has been rewritten.
The new Exim 4 book is available. See the book website for further information.
The O'Reilly Exim 3 book is still available.