Cause of Windows Update Error Code: 0x8004ff91
This Windows Update error code 0x8004ff91 has been occurring due to following reasons.
- Due to firewall blocking.
- The prior installation was improperly carried out.
- Because of third-party antivirus software.
- Due to an unexpected shutdown of the PC during the Windows update procedure.
- Installation of a Windows update is not finished.
- Because of an unexpected system shutdown while Windows Update and installation were taking place.
Note: This 0x8004ff91 error code is Applicable for the Windows XP/7/8/10/11.
Steps to Fix/Resolve Error Code 0x8004ff91
To fix this error code 0x8004ff91, please follow the below simple steps. These actions are for quick solutions. These troubleshooting techniques will repair Windows XP/7/8/10/11.
Step 1: Comprehensive anti-malware scan of the system.
Let’s follow the below steps to resolve this 0x8004ff91 error code for Windows Update.
- Go to the Windows setting.
- Visit the section titled “Privacy and Security”.
- Visit Windows security page.
- visit the threat & virus protection section.
- Pick Scan option.
- After choosing Microsoft Defender Offline scan, click scan now.
- Your computer will soon restart, and a comprehensive scan will begin. (Note: Before restarting your computer, save this page as a bookmark to continue reading.)
Steps 2: To see if any corrupted files exist, run sfc /scannow.
- Press Windows symbol + r.
- Enter cmd and press enter.
- Copy and paste this sfc /scannow then hit enter.
- Wait till it is concluded.
- Run the commands listed below to make absolutely sure everything is functioning properly.
- DISM /Online /Cleanup-Image /CheckHealth
- DISM /Online /Cleanup-Image /ScanHealth
- DISM /Online /Cleanup-Image /RestoreHealth
- Once completed then restart your system.
Steps 3: Launch the Windows Update troubleshooter
- Access Windows Settings
- Visit the Update & security section.
- Pick Troubleshoot from the menu on the left.
- You should notice troubleshooters listed on the right side of your screen (if not, click on Additional troubleshooters or Other troubleshooters).
- Run the troubleshooter by choosing Windows Update and clicking it.
Step 4: Reset the Windows update components
- Launch Command Prompt in Administrator mode.
- Please execute the following commands now:
- net stop wuauserv
- net stop cryptSvc
- net stop bits
- net stop msiserver
- Win + E will launch the File Explorer.
- The following folders contents should be removed:
- Now run the following commands through the Command Prompt:
- net start wuauserv
- net start cryptSvc
- net start bits
- net start msiserver
- Reboot your computer now.
Steps 5: Disable AntiVirus Program
- Open system’s third party antivirus app.
- Click setting.
- Stop or disable your antivirus program till you downloaded and installed windows updates.
Steps 6: Disable the Windows Firewall
- Move on to the Windows Defender firewall settings..
- Disable Windows Firewall.
- Start Windows Update and Installation process.
- You can reboot your PC now.
- Enable Windows Firewall now.
The aforementioned instructions usually work to resolve Windows Update Error Code 0x8004ff91. If the problem still exists, you can do the actions outlined below.
Steps 7: Fix Registry Key
Note: You must have solid troubleshooting skills in order to accomplish the tasks below.
- Go to Windows services.
- Move on to Windows Update Services.
- Click on view Regs key.
- Save the regs key after copying it.
- Now, graciously right-click on the registry key and select repair.
Note: Note: You could save your registry key and update if it didn’t work.
Step 8: Reset your Internet Access
- Launch Command Prompt in Administrator mode again.
- Now, please execute the below commands:
- ipconfig /flushdns
- ipconfig /registerdns
- ipconfig /release
- ipconfig /renew
- netsh winsock reset
- Install Windows Update after rebooting your computer.
In this article, we read about the reason occur this 0x8004ff91 error code and the simple steps to resolve this Windows Update error. We hope the actions above address the Windows Update error code 0x8004ff91. If not, you must deal with a technical professional. If you need rapid live assistance, click on chat to interact with a member of our support staff.