Unexpected end of backup set encountered [V-79-57344-34004]

Hello,

Last night I got this error backing up an Exchange Information Store on one of our mail servers:

 

 

The job continued backing up files, Shadow Copy Components and System State from the same server successfully (that discards problems with the server being backed up).  The backup job even backed up the Information Store on a different mail server, and took only one tape (that discards problems with the media).

Has anybody found a solution to this?  I've seen old posts reporting it but no solution yet.

I would appreciate any help.