Am 08.09.2012 15:43, schrieb bmalik:
i only upgraded dovecot from 1.x to 2.1.x. i didn't change any settings over server. after dovecot service restart, my keep mails on the server, i got again to the outlook. that's my test server but i am going to migrate soon. but i don't want to get duplicate mails. How can i prevent ?
again: you can NOT
POP3 and leave on server depends on the client having a list of message-UUIDs which are already received and it is not uncommon that they are changing due major upgrades on the server
DO NOT LEAVE MAILS FOREVER ON THE SERVER
this is the only solution and will ever be that is why the client offers "delete after X days from server"
smarter clients like thunderbird are defaulting to 14 days not so smart client sleaves their messages forever on the server this is wasting ressources, leads to your troubles and that is why users should learn to look at the options of their sofwtare and try to understand basics who things are working or live with the resulsts if not doing so