Add IMAP debugging config item

Configure inbounce mail: Home / ► Site administration / ► Server / ► Incoming mail configuration / ► Mail settings Add $CFG->debugimap =1; into config.php Run the pickup cron task and see the raw imap commands and responses: php admin /tool/task/cli/schedule_task .php --execute= '\tool_messageinbound\task\pickup_task' Execute scheduled task: Incoming email pickup (tool_messageinbound\task\pickup_task) Connecting to mail.catalyst.net.nz as moodle@moodle.catalyst-au.net... ------------------------------ >> Thu, 03 Mar 2016 22:13:57 +1100 >> Connection to: imap: //mail .catalyst.net.nz:993/ >> Server connection took 3.1834 seconds. S: * OK [CAPABILITY IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA IDLE AUTH=PLAIN ACL ACL2=UNION] Courier-IMAP ready. Copyright 1998-2010 Double Precision, Inc. See COPYING for distribution information. 1 [AUTHENTICATE Command - method: PLAIN, username: moodle@moodle.catalyst-au.net] C: 2 CAPABILITY S: * CAPABILITY IMAP4rev1 UIDPLUS CHILDREN NAMESPACE THREAD=ORDEREDSUBJECT THREAD=REFERENCES SORT QUOTA IDLE AUTH=PLAIN ACL ACL2=UNION S: 2 OK CAPABILITY completed >> Command 2 took 0.0457 seconds. Connection established. C: 3 LIST "" INBOX C: 4 LIST "" tobeconfirmed S: * LIST (\Unmarked \HasChildren) "." "INBOX" S: 3 OK LIST completed >> Command 3 took 0.0437 seconds. S: 4 OK LIST completed >> Command 4 took 0.0849 seconds. Unable to find the 'tobeconfirmed' mailbox - creating it. C: 5 CREATE tobeconfirmed S: 5 NO Invalid mailbox name. >> Command 5 took 0.0419 seconds. Unable to connect to IMAP server. Failed with 'IMAP error reported by server.' ... used 5 dbqueries ... used 3.5641150474548 seconds Scheduled task complete: Incoming email pickup (tool_messageinbound\task\pickup_task) C: 6 LOGOUT S: * BYE Courier-IMAP server shutting down S: 6 OK LOGOUT completed >> Command 6 took 0.0441 seconds.