Hi there, We're running dovecot 2.06, with mdbox. Following message was in our syslog: Jan 20 09:26:48 servername dovecot: [ID 583609 mail.crit] imap(user): Panic: file istream-limit.c: line 79: assertion failed: (v_offset <= lstream->v_size) The problem could be solved on client side, by just deleting the ImapMail-Folder in Thunderbird. Why? Thunderbird tried to move a message, that obviously wasn't there. Dovecot got killed and the message above was in the syslog. Connection was closed and Thunderbird told me the server is dead. Thunderbird tried this every few seconds, and there was no way to say thunderbird "stop try moving". So the only way was to delete thunderbirds mail cache. I think it would be very nice, if dovecot doesn't die, just because the client tries to move a message, which isn't there. Thanks, Tobias Daucher -- Dr. Nagler & Company GmbH Hauptstra?e 9 92253 Schnaittenbach Tel : 09622-7197-38 Fax : 09622-7197-50 Web : http://www.nagler-company.com E-Mail : tobias.daucher at nagler-company.com Hauptsitz: Schnaittenbach Handelregister: Amberg HRB 4653 Gerichtsstand: Amberg Steuernummer: 201/118/51825 USt.-ID-Nummer: DE 273143997 Gesch?ftsf?hrer: Dr. Martin Nagler, Dr. Dr. Karl-Kuno Kunze