1. Unity boots up and sends MAPI notification request to Exchange Servers with Unity Subscribers
2. Message is left for subscriber and is delivered to Exchange Inbox of the subscriber
3. At this point Exchange must send MAPI notification to Unity
4. Unity receives the MAPI notification
5. This triggers a loggin to Subscribers Mailbox to check what has changed in mailbox. The main question: Are there New Voice Messages or No New Voice Messages?
6. Based on this Unity launches process to send MWI on or MWI off notification to Callmanager
In most cases when MWI does not work we are not recieving MAPI notification from Exchange. You can determine this by turning on MWI Macro Traces:
1. Go to Tools Depot > Diagnostic Tools > Unity Diagnostic Tools 2. Click Macro Traces 3. Check 'Traces for MWI problems' and Next and Finish 4. Leave New message and verify the message is in the Exchange Inbox 5. Click 'Gather Log Files' Click 'Select Logs' Expand both AvMsgStoreMonitorSvr and AvNotifierMgr. Collect the last log file for each or the one that contains timestamp for test. 6. In AvMsgStoreMonitorSvr do a search for the Exchange alias of user tested with. Should you fine it for a new message you should see the alias look for Table_Row_Add for new message or Table_Row_Modified for message that was marked as read or Table_Row_Delete for message that was deleted. If you do not see any of this most likely means Exchange did not send or Unity did not receive.
Example:In this case a user called Mickey Mouse dialed into voicemail and moved a message from read to unread. So the MAPI notification from Exchange for this would have been TABLE_ROW_MODIFIED. The Exchange alias for user is MMouse.