[Dovecot] REpeated POP3 mail

[Timo Sirainen]

On Fri, 2010-11-05 at 22:13 -0600, The Doctor wrote:
> > >> You mean POP3 client keeps downloading the same mail again? Usually
> > >> seems to be Outlook bug..
> 
> mail_location = mbox:~/mail:INBOX=/var/mail/%u

Could be because of mbox. If the mbox UIDs change, the POP3 UIDLs
change. Dovecot should log errors if this happens though.

>   pop3_logout_format = top=%t/%p, retr=%r/%b, del=%d/%m, size=%s

You could add ", uidl=%u" to this. It's intended to make it easier to
figure out if the UIDLs are changing or if the client is just being
broken. Then once someone redownloads messages, grep for their last
logout lines and show me what they contain (basically it'll say
uidl=old/new and previous line's "new" should match the next line's
"old" value).