We have had successful backups for a couple to weeks since installation but have just had a job fail with the error listed above.
The account and credentials we use have not changed and when we try the Resource Credentials check in the job properties the test does not run. However the Test Run of the backup job completes OK even when the Credentials check tick box is selected, the Logon account check status reports as successful.
We have reset the password for the account and restarted the services several times but this has had no effect.
The server is SBS2003 R2