I ran into an issue the other day after upgrading some hardware components of our Exchange 2007 server. I was running through the usual connectivity tests after restarting the server and found that Outlook was prompting for authentication before syncing my mail with the server.

Searching through the logs pointed me in the direction of the Exchange services and sure enough one of the services had not started automatically as it should have. The service in question was the Microsoft Exchange System Attendant. Starting this service resolved the issue straight away. I have since restarted the server and the service continues to not start automatically. One to watch…

• Start -> Administrative Tools -> Services
• Right-Click Microsoft Exchange System Attendant service
• Select Start from displayed context menu