In some cases, Avast Antivirus reports that UI Failed to load which stops the whole program from running. This issue may be a result of the incorrect Windows services configuration.
If clicking Restart services on the error message does not help, you need to set the relevant Windows services to run automatically by following the steps in this article.
If after performing all the steps from the instruction above the issue still persists, it is recommended to reinstall Avast Antivirus.
- Refer to the following article for uninstallation instructions:
- After Avast Antivirus is completely removed from your PC, refer to the relevant article for installation instructions:
- Avast Ultimate 17.x
- Avast Premier 17.x
- Avast Internet Security 17.x
- Avast Pro Antivirus 17.x
- Avast Free Antivirus 17.x
- Microsoft Windows 10 Home / Pro / Enterprise / Education - 32 / 64-bit
- Microsoft Windows 8.1 / Pro / Enterprise - 32 / 64-bit
- Microsoft Windows 8 / Pro / Enterprise - 32 / 64-bit
- Microsoft Windows 7 Home Basic / Home Premium / Professional / Enterprise / Ultimate - Service Pack 1, 32 / 64-bit
- Microsoft Windows Vista Home Basic / Home Premium / Business / Enterprise / Ultimate - Service Pack 2, 32 / 64-bit
- Microsoft Windows XP Home / Professional / Media Center Edition - Service Pack 3, 32-bit