Windows Update – and Backup Fail
From Windows for Vista-based computer: “0x80071A91”
To fix this problem, follow these steps:
Click Start, type cmd in the Start Search box, and then right-click cmd in the Programs list.
Click Run as administrator, and then click Continue. If you are prompted for an administrator password or for confirmation, type the password, or click Allow.
At a command prompt, type the following command, and then press ENTER:
fsutil resource setautoreset true c:\
Note These steps assume that Windows is installed in the default location, on drive C. If this is not the case, adjust the drive letter of the folder path to match your configuration.
Restart the computer.