User-Agent: Mozilla/5.0 (compatible; Konqueror/3.2; Linux) (KHTML, like Gecko) Build Identifier: version 0.8 (20040913) I use Thunderbird 0.8 on Linux (RH9-derivative). I am using an IMAP server for local storage (DbMail). I tried to set up a filter so that certain messages get moved directly to IMAP folders on reception. But when I try to get mail, TB says that the filtering has failed "because another operation is in progress". "Receiving" IMAP mail before receiving POP mail does not change things. But manually applying filters later appears to work. This seems to be reliably happening with IMAP folders that were not opened before, or got a large amount of new mail since they were last opened (even by TB copying). Reproducible: Always Steps to Reproduce: 1. Set up an IMAP account and a POP account 2. Set a filter from the POP acount's INBOX to the IMAP account's folder. 3. Put some 1,000 messages into the same IMAP folder, don't open it with TB. 4. Send a mail that will suit the filter to the POP account. 5. Receive mail on the POP account Actual Results: A message informing that the filtering has failed "because another operation is in progress". Expected Results: Move the message to the IMAP folder

See in particular bug 210614 comment 5. *** This bug has been marked as a duplicate of 210614 ***