Andrew Gargan wrote:
> Hi
> 
> I am having problems with users accessing their maildir mail stores 
> through dovecot
> I am working on version 0.99.11-1 (on fedora core)

At the very least, you should look for version 0.99.14, as there were a 
considerable number of fixes between these versions.

If possible, current wisdom is to recommend the 1.0-stable branch, which 
has far too many improvements to list here.

> It seems to be when the email size is large (450KB +)

Are you using mbox or Maildir storage?

> The errors are (the server disconnected unexpectedly)
 > Have read through logs and looked for clues but am just getting no 
where ...

Do you have logging turned up full?

> Have turned on the three Outlook and Outlook Express workarounds I found 
> but no luck.

Heh... I turned these _off_ last week... but we have a company policy 
that OutLoo is not allowed.  If people complain to me, I get to tell 
them they can't be having problems with it, because they can't be using 
it. Ah, the joys of having Engineers as company directors. :)

> All the linux boxes here seem to be able to handle things fine ... 
> (kmail evolution etc.)
> 
> Thunderbird is also giving me hassles when trying to pull large mail files.

Almost all my users run Thunderbird, no problems.  Even when marketing 
decides to send a 9MB file to someone.

> The server is a 2.8 P4 HT with 1024 MB RAM 200GB SATA RAID.
> +- 7 domains and +-1200 users.

Plenty of grunt, then.  I'm assuming some Linux variant... FC perhaps?

> Squirrel Mail seems fine and users are using that to get around the 
> problem for now but I really need the pop3 access working ...

Such a popular tool... if only it weren't written in PHP.

> My MTA is postfix and I am using virtual mailboxes using mysql_lookups.
> 
> I am also running MailScanner and ClamAV and SpamAssassin (using the 
> hold queue method)

For once, someone providing an excess of information.  Good work :)

--
Curtis Maloney

Andrew Gargan

Developer

Interface Media (PTY) Ltd.

Tel: 011 507 3003