Resolve Avast Error Code 0x8009000bu

 Avast Error Code 0x8009000bu

The Avast error code 0x8009000bu occurs during the boot-time scan.

Steps To Fix The Error

  • If you have any other security or firewall program on your computer, disable it.
  • Turn off Real-Time protection on Windows Defender from Settings.
  • Open the Avast user interface.
  • Click on Menu and go to Settings.
  • Choose the General tab and navigate to the Troubleshooting section.
  • Now, click on the Repair button and restart Avast. Check if the error has been fixed.
  • If it persists, then you have to uninstall and reinstall Avast on your computer.
  • Make sure to sync your data before uninstalling Avast.
  • Open the Control Panel window and go to the Programs and Features section.
  • Now, select the Avast program and click on the Uninstall button.
  • If you are unable to remove the program, you can use the Avast removal tool to delete it from your computer completely.
  • Once you have uninstalled Avast, restart your computer. This will be an essential one to fix Avast error code 0x8009000bu.
  • Now, proceed to download the latest version of Avast.
  • Open a web browser on your computer and go to the Avast website, choose your region, and select the latest version of Avast. Click on the Download button.
  • Once the download is complete, run the installer file.
  • Install the Avast antivirus program by following the instructions on the setup wizard.
  • Now, launch the Avast program on the computer.
  • Navigate to the Privacy tab on the left panel of the screen.
  • Click the Passwords icon on the right panel.
  • Click the Settings icon on the top-right corner of the screen.
  • Select the Sync & backup menu and then click on the toggle switch to turn on syncing.
  • In case you have not logged in to your Avast account, log in to it using the right credentials.
  • Now, the Avast error code 0x8009000bu should be fixed on the computer.


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