SharePoint logon error

[ex5o5er]

I have a small sharepoint farm that I am trying to backup.  However, I get the following intermittent error the causes the job to fail:

SharePoint -- The job failed with the following error: The logon account that was provided does not have valid credentials. Ensure that the user name and password are correct, and then try again.

I have not changed the logon account.  If I try to check the credentials, quite often BackupExec will crash and will require a restart.  If the program does not freeze, the credential check succeeds.

How do I get this job running again? 

[newsolutionBE]

Hi

Please check  link below

http://www.symantec.com/docs/TECH168587

If it is CASO MMS enviorment then check this link

http://www.symantec.com/docs/TECH168353

[ex5o5er]

I have checked the credentials listed in the link of the last post and all is as it should be.  I am still getting this error message preventing the backup job.

Backing up the farm manually works fine using Central Administration.