Avast is the best and most well-known antivirus software for desktops and mobile devices. This premium, cost-free protection protects your devices from hazardous applications or asks your permission for them. Unfortunately, many Avast Antivirus users complained that they are dealing with Virus Definition Update Failed errors on both the premium and free versions.
The main cause of Avast virus definition update failed errors are corrupted cache data or outdated versions of applications and sometimes it can trigger due to an unstable internet connection so make sure you should have an active and stable internet connection.
If your internet connection is perfectly fine and you still facing the error then calm down. In this article, we have explained effective solutions to resolve the Avast virus definition update failed error.
How To Fix Avast Virus Definitions Update Failed Error on Desktop PC?
Read this guide if you dealing with Virus definition Update failed error on Avast mobile
1. Manually Update Avast Virus Definitions and the Avast App
If automatic updates of Avast virus definitions are not working then you can go for automatic updates. Updating the Avast app from time to time will keep your device protected from bugs. To update it manually follow the process:
- Open Avast on your system.
- From the top-right corner of the window, click on the Menu of the app.
- Then navigate Settings and then General
- Then click on the Update option from the side list.
- Now choose the Check for Updates option under the Virus definitions are up to date section.
- Then wait until Avast will find new virus definitions.
- Choose Check for Updates under Your application is up to date section.
If the Avast update fails, you may be using a faulty proxy server. By choosing More options next to Your application and unchecking the Use particular proxy server box, you may disable this proxy server. Then, attempt to upgrade the app once again.
2. Repair the Avast App
Avast antivirus comes preloaded or we can say built-in repair tool with a repair option which has a great advantage in fixing the definitions update failed error. Once you will run it, Avast repair itself.
- Open Avast on your system.
- From the top-right corner of the Avast window, click on the Menu of the app.
- Then navigate Settings and then General
- Then click on the Troubleshooting option from the side list.
- Find the Still having problems section by scrolling down.
- Choose the Repair App option.
- Then select Yes to confirm and restart your system when Avast is repaired.
3. Turn Off the Windows Firewall
Sometimes firewall blocks the connection of Avast to the virus definition servers resultantly Avast is not able to update its virus database. To Disable the firewall temporarily follow the process:
- First of all, open the Control Panel and choose the System and Security option.
- Select the Windows Defender Firewall and then from the left sidebar, click on the Turn Windows Defender Firewall on or off option.
- Under both Private and Public network settings sections enable the Turn off Windows Defender Firewall option and choose the OK button from the bottom.
- Finally, try running a manual virus definition update by Starting Avast.
4. Fix Your Date and Time Settings
Incorrect date and time Settings can also cause the Avast virus definition update failed error. To set it follow the procedure:
- By pressing Windows + I keys together, open Settings on your Windows PC.
- Choose Time & Language option and then from the left sidebar Date & time.
- Lastly, enable Set time automatically and Set time zone automatically options by clicking on them.
5. Reset Avast Settings
Avast has several tools and configuration choices included. Any improper setting may result in problems with the program and prevent it from updating its virus definitions. Fortunately, Avast provides a choice to instantly return all selections to their normal settings. Remember that once you have reset Avast, you will need to change your settings.
- Open Avast on your system.
- From the top-right corner of the Avast window, click on the Menu of the app.
- Then navigate Settings and then General
- Then click on the Troubleshooting option from the side list.
- Find the Reset all settings section by scrolling down.
- Choose the Reset to Default option.
- Lastly, choose Yes then try running a manual virus definitions update in Avast.
6. Reinstall Avast
If all of the above methods did not work then try reinstalling the Avast after uninstalling It by following these steps:
- Open the Settings of your Windows PC.
- Choose Apps and then select Avast from the list.
- Then click on the Uninstall button for Avast.
- Choose Uninstall from the mini window that will appear.
- Restart your system after uninstalling Avast.
- Redownload the Avast and install Avast on your system.
