Ошибка установки – 0x800f0991 при включении обновления

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The error code 0x800f0991 typically occurs on Windows when there are issues enabling certain features, particularly related to Windows Updates or Windows features.

Here are some steps you can take to troubleshoot and resolve this issue:

1. Run Windows Update Troubleshooter:
Press Windows + I to open Settings.
Go to Update & Security.
Click on Troubleshoot.
Select Additional troubleshooters.
Click on Windows Update and follow the prompts.

2. Check for Pending Updates:
Sometimes, pending updates can cause conflicts.
Go to Settings > Update & Security > Windows Update, and see if there are any updates available. If so, install them and then try again.

3. Use the DISM Tool:
Open Command Prompt as an administrator (search for cmd, right-click it and select Run as administrator).
Run the following command to check the health of your system:
DISM /Online /Cleanup-Image /CheckHealth
If it finds issues, you can attempt to repair it:
DISM /Online /Cleanup-Image /RestoreHealth

4. Run SFC (System File Checker):
After running DISM, you should run the System File Checker to scan for and repair corrupted system files:
In the same Command Prompt window, enter:
sfc /scannow
Wait for the scan to complete and follow any on-screen instructions if issues are found.

5. Check Windows Services:
Ensure that necessary Windows services are running:
Press Windows + R, type services.msc, and hit Enter.
Ensure the following services are running:
Windows Update
Background Intelligent Transfer Service
Cryptographic Services
If any service is not running, right-click and select Start.

6. Manually Enable the Feature via PowerShell:
If the error occurs while enabling a specific Windows Feature, you might try enabling it directly via PowerShell:
Open PowerShell as administrator.
Use the following command to enable the feature (replace with the actual feature name):
DISM /Online /Enable-Feature /FeatureName: /All

7. Clear Windows Update Cache:
Sometimes the Windows Update cache can become corrupted. You can clear it by:
Stopping the Windows Update Services:
net stop wuauserv
net stop cryptSvc
net stop bits
net stop msiserver
Deleting the cache data:
Navigate to C:\Windows\SoftwareDistribution and delete all files and folders in this directory.

Restart the Windows Update Services:
net start wuauserv
net start cryptSvc
net start bits
net start msiserver

8. Perform a Repair Install:
If the above solutions do not resolve the issue, you may consider performing a repair install of Windows 10 or Windows 11 to effectively reset the system files without losing your data.

9. Consult Microsoft Support:
If you've tried everything with no success, consider reaching out to Microsoft Support for further assistance.
Before proceeding with troubleshooting steps that involve system changes, always ensure that you've backed up important files and data.

If you need further assistance, please don't hesitate to contact us!