When SQL Server 2005 Management Studio's Object Browser shows the SQL Server Agent service with a red down arrow and the text Agent XP's disabled , the service is not started or disabled. This used to be a problem prior to Service Pack 2 for SQL Server 2005, obviously SQLAgent is important part...
MSDTC - Microsoft Distributed Transaction Coordinator should be installed (Service up and running) when executing the BEGIN DISTRIBUTED TRANSACTION statement that controls the completion of the transaction. So to complete this transaction with a subsequent COMMIT TRANSACTION or ROLLBACK TRANSACTION statement...