Problem: While archiving IMAP mailboxes the error unable to parse server response occurs.
Solution: Although this error message is generic, some IMAP server related issues and solutions are known:
- MDaemon: Sometimes the MDaemon server just return UID 0 for a message while fetching the list of UID for a particular folder. UID 0 is not allowed by the IMAP RFC. The fix is to delete the IMAP.MRK file from the folder on disk. This will cause the IMAP server to re-index all messages (losing all IMAP flags -- All messages will become UNSEEN and UNREAD). If you want to preserve flags, messages can be moved to another folder using IMAP or webmail first, then delete the IMAP.MRK and restore the messages.