The mail server is Exim 4. It is configured to filter incoming email for viruses (using ClamAV) and spam (using SpamAssassin). Any email found to contain a virus will be rejected. Email found to be spam will only be rejected if it is regarded as being very likely to be spam (as determined by the number of points assigned to it by SpamAssassin). Email scoring a moderate number of points will be tagged as spam through the addition of X-Spam-Flag, X-Spam-Report, and X-Spam-Score headers, but not rejected.
Domain Hosting / Mail forwarding
If your user account is associated with a hosted domain then your home directory will contain an 'email' subdirectory. Inside that directory will be a file with a name corresponding to the hosted domain. This file is an Exim redirection list that controls mail forwarding for the domain. This file must be readable by the mail server and must not be deleted or renamed, if the mail server cannot read this file then email for your domain will no longer function. Any changes to this file will take effect instantly.
Redirection file format
Each line in the redirection file maps an email address local part (the bit before the '@'-sign) at your domain to one or more email addresses that the email should be forwarded to. There should be whitespace or a colon followed by whitespace between the local part and the address (or list of addresses seperated by commas) to which the email should be forwarded. For example you might have a file named yourdomain.com containing:
management: email@example.com, firstname.lastname@example.org
The special local-part * can be used as a default, it will match any address that is not matched by another line in the file. For example:
There are a few supported special destinations too, for example :fail: - which will force email to the matching address to be rejected. E.g.:
X.Employee: :fail: Gone away, no forwarding address
Exim is configured to support optional 'suffixes' on the local part of email addresses, meaning that the local part of the address may by followed by a hyphen and then any text. In the above example this means the address email@example.com will behave like firstname.lastname@example.org and be forwarded to email@example.com. This feature allows users to give out unique email addresses to many different people or companies, for example when filling in registration forms on websites. It is then possible to monitor how this address is used and to block it if it is misused (by adding a line such as 'john-smellycompany: :fail:' into the redirection file).
If John's ISP (hisisp.net in the example) also support this feature then it is possible to amend John's line in the redirection file to:
In this case firstname.lastname@example.org will be forwarded to email@example.com as normal, while firstname.lastname@example.org will magically be forwarded to email@example.com.
The address abuse@yourdomain cannot be overridden in the redirection file. Email to this address will always be sent to the system administrator.
If you have an account on your server then you'll be able to access your email via IMAP and send messages via SMTP. Email clients should be set up with the following details:
IMAP Server: mail.randomstuff.org.uk
IMAP Port: 993 (use SSL)
IMAP Authentication: Plain text
SMTP Server: mail.randomstuff.org.uk
SMTP Port: 587 or 25 (use TLS) or 465 (use SSL)
SMTP requires authentication: Yes
As an example, here are the settings for Windows Live Mail 2012: