I configured Data Protection Manager to protect single Exchange Mailbox database.
Since then no backup operation completed successfully and I always have the following State.
As both of the Event-logs gave the same result that the error is because of the exchange database logs, here i remembered that i enabled the circular logging on my environment. and by fast googling i found the following subject that emphasis my point of view http://blogs.technet.com/b/dpm/archive/2010/09/02/dpm-backup-of-exchange-databases-can-fail-because-of-exchange-circular-logging.aspx
Hint: I enabled Circular logging as I was moving Mailboxes Between Databases to prevent creating logs for Messages that already stored in the database.
To solve the problem:
1- Disable Circular logging on the protected Mailbox Database.
2- restart the information store service or you can ( dismount/ mount ) the mailbox database.
IF you still have the same problem the cause for this might be that you’re using Exchange 2013, then all what you have to do is installing Visual C++ Redistributable for Visual Studio 2012 Update 4 on both DPM and Exchange servers.
Get Visual C++ http://www.microsoft.com/en-us/download/details.aspx?id=30679