Ok, it seems i found the problem, i was missing the plugin declaration into dovecot.conf
imapc_host = mail.foo.com imapc_features = rfc822.size pop3c_host = mail.foo.com namespace { separator = / inbox = yes } protocol doveadm { mail_plugins = $mail_plugins pop3_migration } disable_plaintext_auth = no pop3_uidl_format = UID%u-%v And then using command: *doveadm -o imapc_user=foo -o pop3c_user=foo -o imapc_password=bar -o pop3c_password=bar backup -R -u user at domain <http://dovecot.org/cgi-bin/mailman/listinfo/dovecot> pop3c:* The only doubt i have is how to sync both imap and pop3, i've seen that if i made a pop3c sync ath then impac sync gives an error, and if execute imapc and then pop3c it gives an error too. 2013/9/2 nik600 <nik...@gmail.com> > to give some more information, i've set > > pop3_uidl_format = UID%u-%v > > on the courier-side i get this UIDL answer: > > UIDL > +OK > 1 1378040847.Vfe11I12801312M172099.myserver.cloud923 > 2 UID2-1378040947 > 3 UID3-1378040947 > 4 UID4-1378040947 > 5 UID5-1378040947 > > > on the dovecot-side i get this UIDL answer: > UIDL > +OK > 1 UID1-1378127599 > 2 UID2-1378127599 > 3 UID3-1378127599 > 4 UID4-1378127599 > 5 UID5-1378127599 > > > > > > 2013/9/2 nik600 <nik...@gmail.com> > >> Dear all >> >> i'm planning a transparent migration from a courier server that provides >> both IMAP and POP3 access to users to a remote dovecot server with both >> IMAP and POP3 access. >> >> I have to migrate about 2500 users for 250 GB of space. >> >> I'm using dovecot 2.2.5.4 on debian6 squeeze. >> >> To make a transparent migration i have to maintain old IMAP UIDs and POP3 >> UIDs, so i've read >> >> http://wiki2.dovecot.org/Migration >> and >> http://wiki2.dovecot.org/Migration/Courier >> and >> http://wiki2.dovecot.org/Migration/Dsync >> >> And decided that probably the best tool to use is Dsync, as the >> courier-dovecot-migrate.pl<http://www.dovecot.org/tools/courier-dovecot-migrate.pl> >> script >> works only locally. >> >> I've tested the dsync following instructions reported above but after the >> migration of one test-account the client re-download messages. >> >> >> If i want to keep both IMAP UIDs and POP3 UIDs i have to sync both imapc >> and pop3c with two commands? >> >> doveadm -o imapc_user=foo -o pop3c_user=foo -o imapc_password=bar -o >> pop3c_password=bar backup -R -u user@domain imapc: >> >> doveadm -o imapc_user=foo -o pop3c_user=foo -o imapc_password=bar -o >> pop3c_password=bar backup -R -u user@domain pop3c: >> >> >> Or imapc is enough? >> >> Do you have any suggestion? >> >> Thanks >> >> -- >> /*************/ >> nik600 >> http://www.kumbe.it >> > > > > -- > /*************/ > nik600 > http://www.kumbe.it > -- /*************/ nik600 http://www.kumbe.it