FIX: Windows Update Error 0x80071a91

Reports from users about receiving error 0X80071a91 while running a Windows update are increasing. This situation can become quite critical if there are pending, crucial updates, potentially leaving your computer outdated. Error 0x80071a91 essentially translates to ‘Transaction support within the specified file system resource manager is not started or was shutdown due to an error.’ This error is mainly attributed to the service named File System Resource Manager (FSRM) being overwhelmed. However, other causes can contribute to this error, which will be addressed in the following guide.

Solution 1: Reset FSRM

In this method, we will simply reset File System Resource Manager (FSRM), through command prompt.

To do that, press Windows key and type cmd. In the search results, right click on cmd, and choose Run as administrator. In the black command prompt window, type the following command and press Enter:

fsutil resource setautoreset true C:\

C: is the drive where your Windows is installed.

After the command runs successfully, restart your system and run the Windows updates now.

If you get the error again, then move on to the next method,

Solution 2: Deleting Common Log File System (CLFS) transaction logs

When Common Log File System (CLFS) transaction logs are in a corrupt state, they can cause this error in Windows updates. We will simply delete them, and Windows will create a fresh copy.

To do that, press Windows key and type cmd.

In the search results, right click on cmd, and press Run as administrator.

In the black command prompt window, type the following commands and press Enter after each command:

cd /d %SystemRoot%\System32\SMI\Store\Machine

attrib -s -h *

del *.blf

del *.regtrans-ms

If you encounter an error stating that these files are in use, restart your system and try again. If the error persists, download Unlocker from this provided link. After downloading, run the file and install Unlocker.

Press and hold the Windows key, then press R. In the run dialog, type %SystemRoot%\System32\SMI\Store\, and then press Enter. Right-click on the ‘Machine’ folder and select ‘Unlocker’. If it is in use, then select ‘Unlock All’.

Now try the commands above to delete the files,

Restart your system at the end and check if the issue is resolved. If not, proceed to the next solution.

Solution 3: Run Windows Update Troubleshooter.

Please proceed to the following link: http://go.microsoft.com/?linkid=9830262.

The troubleshooter will download. If you can run/open it directly, click ‘Run/Open.’ If not, download it first and then run it.

Click ‘Windows Update’ in the troubleshooter window, then click ‘Next’.

It will automatically detect and fix errors it finds.

Restart your system and check if the error’s gone.

If not, move on to the next solution.

Solution 4: Restart Windows Update Services

The BITS service, the Windows Update service, and the Cryptographic service are all services that the MSI Installer involves in Windows update. Any one of them can individually malfunction and cause this error. However, we will restart all of them to remove any doubt. Click here to download the windowsupdateservices.bat file, then right-click on it and choose ‘Run as Administrator.’

If the update script opens as a text file, save it as a .bat file. Then, right-click and choose ‘Run as Administrator’, or copy the commands and paste them into the command prompt (admin).

Solution 5: Reregister Windows update files

In this step, we will re-register the BITS files and the Windows Update files. Click here to download the Windows Reg Update, right-click on it, and choose Run as Administrator.

Solution 6: Rename Corrupt Update Stores

Sometimes, this error can be triggered by previously failed updates. It is recommended to rename the old stores, allowing Windows to attempt updates in a new, clean folder.

To do this, press the Windows key to open the Start menu (Search) and type ‘cmd’.

In the search results, right click on cmd, and choose Run As Administrator.

In the black command prompt window, type the following commands and press Enter after each command:

ren C:\Windows\SoftwareDistribution SoftwareDistribution.old

ren C:\Windows\System32\catroot2 Catroot2.old

C: is the drive where you have installed Windows.

Now restart and check if the issue is resolved.