1. Download the utility from http://www.mailenable.com/Tools/MEQueueClean.zip 2. Extract and copy the exe file to \Mail Enable\Bin\ For Plesk installation. The MailEnabke directory will be under Program Files (x86)\Parallels\Plesk\Mail Servers\Mail Enable 3. Check the message source by opening checking the mail queue folder Mail Enable\Queues\SMTP\Outgoing\Messages