Please post the exact error message, and the output of dovecot -n
This way it is much easier for people to help you, and it takes less guessing what is going on.
Sorry, here's the full details.
Maillog says
Jun 25 19:10:55 test1 dovecot: imap(tu2): Error: stat(/var/mail/attachments/04/f6/.temp.test1.vmlan.local.1522.2cde9668dcad3fd5) failed: Permission denied Jun 25 19:10:55 test1 dovecot: imap(tu2): Error: safe_mkstemp(/var/mail/attachments/04/f6/.temp.test1.vmlan.local.1522.) failed: Permission denied
This is when attempting to export the same mail to two accounts. As the first user "tu1" get to own the attachment dirs, the second user "tu2" is denied permission.
Eg: drwx------ 3 tu1 tu1 4096 Jun 25 19:10 f6
# 2.0.13: /etc/dovecot/dovecot.conf # OS: Linux 2.6.18-238.9.1.el5 x86_64 CentOS release 5.6 (Final) auth_debug = yes auth_debug_passwords = yes auth_verbose = yes disable_plaintext_auth = no mail_attachment_dir = /var/mail/attachments mail_attachment_min_size = 1 k mail_location = sdbox:~/dbox mbox_write_locks = fcntl passdb { driver = pam } ssl_cert =