This is due to the exchange writer server being off. You will get this in backup exec and the information store will not be backed up properly. Here is the solution
- Click Start, click Run, type regedit, and then click OK.
- Locate and then double-click the following registry subkey:
- Double-click the Disable Exchange Writer value.
- In the Value data text box, change the value from 1 to 0, and then click OK.
- Quit Registry Editor.
- Click Start, point to Administrative Tools, and then click Services.
- Stop and then restart the Microsoft Exchange Information Store service.