Disable third-party antiviruses
The built-in Windows Defender is enough for computer protection. If you have third-party antivirus software installed on your PC, it’s a good idea to disable or uninstall it before running Windows 11 Installation Assistant, as many third-party antivirus software can interfere with the installation assistant.
The steps to temporarily disable your antivirus program will vary depending on the program. Disable the antivirus during the upgrade process, and grant Administrator access when prompted.
Perform an SFC Scan
This problem may occur when important system files become corrupted. If you are not sure if any system files are corrupted, just run System File Checker (SFC). You can fix system file corruption by running SFC.
- Run Command Prompt (CMD) as Administrator. You can open it in the Start Menu and in the search box say “cmd“, then right-click and select “Run as administrator”.
- In the CMD window type, the following command and press Enter.
sfc /scannow
For more detailed ways, you can see in our other article How to fix Corrupted Windows System Files with System File Checker (SFC) scannow
Restore Windows System Defaults
Some Windows users remove bloatware to improve performance. Configuring Windows as you need and disabling services you don’t need will have a huge impact on improving Windows performance.
You can do this by tweaking applications or others. However, this system configuration change can cause an error code to appear at 0x8007007f when you upgrade to Windows 11.
To fix this problem, simply restore the Windows configuration to its default settings using the same application when you made the changes.