In my case, I am running Microsoft CRM 1.2. One server is handling the SQL and web service duties and another machine is my Active Directory and Exchange server. On my AD/Exchange server, I started getting tons of errors in my Event Viewer, even though I was not really noticing any problems with the system. Along with this event, I was getting Event ID 5896 and Event ID 5897 from the same source. It turned out to be an easy fix. The password for the account that was running the "Microsoft CRM Exchange Queue Service" on my AD/Exchange server expired. Once I set the new password and restarted the service, the problem was solved.
This event also happens when the password for the account that is being used to run the service has expired.
This problem appears because the Microsoft CRM Exchange Queue Service is not running as a user with administrative privileges to Exchange (in this case LocalSystem). Change the Microsoft CRM Exchange Queue Service to run as a user with administrative privileges to the Exchange server.