SQL Server agent connection problem

[TimGowen]

Since upgrading a SQL Server to Windows Server SP2 I cannot get Backup Exec to connect to the database and back up.

The error is:

Event Type: Error
Event Source: Backup Exec
Event Category: None
Event ID: 57860
Date:  29/03/2007
Time:  12:22:38
User:  N/A
Computer: DOMINIE
Description:
An error occurred while attempting to log in to the following server: "DOMINIE\EVENTSPERFECT".
 SQL error number: "4814".
 SQL error message: "Login failed for user 'MM\Administrator'. Reason: Not associated with a trusted SQL Server connection.
".

 For more information, click the following link:
http://eventlookup.veritas.com/eventlookup/EventLookup.jhtml
Data:
0000: 14 48 00 00 00 00 00 00   .H......
0008: 00 00 00 00 00 00 00 00   ........

I have verified that the password is entered correctly in credential manager.