This is an old revision of the document!

Every incoming e-mail is filtered by some e-mail filter rules, based on a language called Sieve and you can manage them using webmail service (horde or squirrel).
The old one, based on Procmail, is now disabled.

E-mail filters rules include: vacation, forward, spam filters, general filter rules. These 4 points (your main filter settings included) can be managed using the web interface of Horde or SquirrelMail ONLY.
All e-mail clients (pine, thunderbird, etc.) filter rules work after the rules managed through horde or squirrel, so any e-mail client can not overwrite or overtake the rules fixed/managed through webmail service

But remember that the settings defined using horde are not exportable to squirrel and viceversa.
If you define a rule, this will be active until when you change or overwrite it. The activated filters are the ones which have been saved for last.

This means for example that:

• setting/modifying a configuration (filters too) using squirrel will overwrite horde rules and viceversa. So manage your configuration using always horde or always squirrel. For example: you have NOT to set forward and vacation with horde and then spam filter settings with squirrel… or viceversa.
  
• but your can read/send/manage your e-mails using squirrel, and use the filter settings set through horde without any problem.

To avoid any problem, to modify/enable/disable your e-mail filter rules use always the same webmail service. NOT BOTH!!