Just to make sure, the Rebex log contains much more information. If you create a Rebex log using the Imap LogWriter property with the default LogLevel (i.e. LogLevel.Debug) , there will be logged the communication between your Imap server and Rebex Imap client. The portion that you posted above, is only a stack trace of the actual exception that was raised by the CopyMessage method in your program. To be able to tell more, we need to see the full log. See my answer below for explanation why you get the ImapException.
