We have had a couple of cases recently where the IMAP synchronisation process in Outlook 2013 seems to go nuts. The client system APPENDs large numbers of messages stored on the user's local hard disk to the Cyrus inbox and then deletes and expunges them (one at a time). It does this repeatedly. "X-OlkEid:" in the message headers and MIME multipart boundary markers in the body are different in each message, so the additional messages aren't exact copies. (I guess this could be some kind of broken filter rule. At the moment I'm working with third hand information). In one case the client managed to generate a 3.5 GByte cyrus.cache file (with about 1.5 million recently expunged messages), which is dangerously close to the 4 GByte limit on that file. We are running Cyrus 2.4.17. I appreciate that this isn't really a Cyrus question: I was just hoping that someone somewhere had seen the same effect and had worked out how to make Outlook behave. A Google search suggests that Microsoft "improved" the IMAP support in Outlook 2013, but I haven't found a specific match to the symptoms that I am seeing. -- David Carter Email: David.Carter@xxxxxxxxxxxxx University of Cambridge, Phone: (01223) 334502 Information Services, Fax: (01223) 334679 7 J J Thomson Avenue, Cambridge UK. CB3 0RB ---- Cyrus Home Page: http://www.cyrusimap.org/ List Archives/Info: http://lists.andrew.cmu.edu/pipermail/info-cyrus/ To Unsubscribe: https://lists.andrew.cmu.edu/mailman/listinfo/info-cyrus