When you try to perform a backup on a Windows Vista-based computer by using the Automatic File Backup feature, you receive the following error message:
File backup could not save your automatic backup settings for the following reason: Transaction support within the specified file system resource manager is not started or was shutdown due to an error. (0x80071A91)
This issue occurs if the Windows file system transaction log is corrupted. The Windows file system uses the transaction log to recover system transactions when a file error occurs.
This article is based on a Microsoft KB 939399 or more information please visit the below given link