Alex Ruben
How to Resolve Windows Update Error Code 0x800f0991
If you’re encountering Windows Update Error Code 0x800f0991, you’re not alone. This common error often arises from missing or corrupted system files, or issues within the Windows Update process. In this guide, we will walk you through a series of steps to diagnose and fix the error, enabling you to successfully update your Windows system. By following this tutorial, you will learn how to restore the functionality of your Windows Update process on Windows 10 and Windows 11, whether on a PC, desktop, or laptop.
Before proceeding, ensure that you have administrative privileges, as some steps will require elevated permissions. Also, it’s wise to back up any important data, as troubleshooting can sometimes lead to unintended changes in system settings.
Step 1: Start Essential Windows Services
The first step in resolving this update error is to ensure that the necessary Windows services are running. Follow these steps:
- Press Windows + S to open the search bar and type services. Click on the Services app.
- In the Services window, locate the Windows Update service. Double-click it to open its properties.
- Set the Startup type to Automatic and click Start to ensure the service is running. Click OK to save your changes.
- Next, find the Background Intelligent Transfer Service and repeat the above steps: double-click, set to Automatic, start the service, and click OK.
- Finally, look for the Cryptographic Services, and again set it to Automatic, start it, and click OK.
Step 2: Run the Windows Update Troubleshooter
If the error persists after ensuring the services are running, the next step is to use the built-in Windows Update troubleshooter:
- Open the search bar again and type troubleshoot settings. Click on it.
- In the Troubleshoot window, select Other troubleshooters.
- Scroll down to find Windows Update and click the Run button next to it.
- Allow the troubleshooter to complete its scan. If it detects any issues, it will offer to fix them automatically.
Step 3: Check System Files Using Command Prompt
If troubleshooting did not resolve the issue, it’s time to check for corrupted system files using the System File Checker (SFC) tool:
- Press Windows + S to open the search bar and type cmd. Right-click Command Prompt and select Run as administrator. Click Yes if prompted for permission.
- In the Command Prompt window, type the following command and press Enter:
- Wait for the scan to complete. It may take some time. If any integrity violations are found, the tool will attempt to repair them.
sfc /scannow
Step 4: Use DISM to Repair Windows Image
Should SFC not resolve the issue, the next step is to use the Deployment Imaging Service and Management Tool (DISM) to repair the Windows image:
- In the same Command Prompt window, type the following command and press Enter:
- Allow the DISM tool to complete its process. This may also take some time depending on the state of your system.
DISM /Online /Cleanup-Image /RestoreHealth
Step 5: Restart Your Computer
Once all commands and troubleshooting steps have been completed, restart your computer. This ensures that any changes made during the troubleshooting process are properly applied and allows for a clean start of the Windows Update service.
Extra Tips & Common Issues
While following these steps, keep in mind the following tips:
- If you still experience issues, consider disabling any third-party antivirus software temporarily, as it can sometimes interfere with the update process.
- Make sure your system has enough disk space available, as insufficient space can also cause update failures.
- Keep your Windows version up to date by periodically checking for updates, as newer updates may fix underlying bugs.
Conclusion
By following the steps outlined in this guide, you should be able to resolve Windows Update Error Code 0x800f0991. Regular maintenance of your system’s update settings and services can prevent similar issues in the future. For further assistance or guidance, feel free to explore more optimization and troubleshooting guides.
Frequently Asked Questions
What causes Windows Update Error Code 0x800f0991?
This error typically arises due to missing or corrupted system files, or conflicts within the Windows Update services.
How can I prevent Windows Update errors?
Regularly check for updates, maintain sufficient disk space, and ensure that essential services are running can help prevent errors.
Can I fix Windows Update errors without an internet connection?
While some steps may be completed offline, having an active internet connection is recommended for downloading any necessary updates or files during troubleshooting.