Hi mikebeck,
Just answered your question if the imap is enabled and any error in the log. IMAP is enabled, and no error in the log.
Well, I use the method described http://cheleguanaco.blogspot.com/2010/04/sugarcrm-troubleshooting-imap.html.
It is found that the connectivity to mail server is ok, but the return shows the total number of messages is 0.
Actually it is not 0. Anything wrong? Can it cause the ‘test setting’ not working?