[Dovecot] Disallow POP3 from deleting messages

[Robin]

On 3/20/2013 6:35 AM, DormitionSkete at hotmail.com wrote:

> Well, like I said, we have real slow upload speeds.  I think POP3 would give a better user experience.

About the only connectivity situation where POP3 might make for a better 
"user experience" is one of intermittent bursty sort that's prone to 
reliability issues.

IMAP provides for header-only enumations as well as partial body fetches 
on demand, as opposed to "all or nothing" POP3 access.  With a suitable 
modern caching client, it will not re-download emails already viewed. 
I've never used any of the devices you mentioned, so I can't speak to 
how their mail clients are implemented.

> We're using sendmail.  I assume this is done in sendmail, not Dovecot?

No, sendmail is a Mail Transport Agent (MTA), which is akin to the 
Postal Service.  All it does is convey emails from one endpoint to 
another as reliably as possible.  What is done with the mail once it's 
at that endpoint is left to the "consumer" of the mail, in this case, 
the Mail User Agent (MUA).  It can be automatically processed/filed like 
via procmail or LMTP, or managed via the client through POP3 or IMAP4.

Your main concern sounds like performance from users who connect from 
outside of your enterprise network, which may happen even when your 
mobile devices are on site, due to the way they obtain their 
connectivity?  Timo's replication idea is sensible to address that problem.

Good luck!
=R=