Updating virus definitions and Avast Antivirus application version

Avast Antivirus uses a database of known virus definitions to identify malware and other threats on your PC, which is why it is important to ensure the virus definitions are regularly updated.

Application version refers to the user interface and all Avast Antivirus components. Updates to the application version provide bug fixes and general improvements.

By default, Avast Antivirus is set to update the virus definitions and application version automatically. We strongly recommend you keep automatic updates enabled.

This article provides instructions on how to manually update virus definitions and the Avast Antivirus application version, as well as how to manage the automatic update options.

Manually update virus definitions

1. Right-click the Avast icon in the notification area of your Windows taskbar and select Update ▸ Engine and virus definitions.
2. If your Avast Antivirus doesn't begin checking for updates automatically, click Check For Updates.
3. Wait while your Avast Antivirus checks for virus definition updates.
4. When the update is complete, you will see that Virus definitions are up to date.
5. You may need to restart your PC to complete the update. If prompted, click Restart Now to reboot immediately.

Manually update the application

1. Right-click the Avast icon in the notification area of your Windows taskbar and select Update ▸ Program.
2. If your Avast Antivirus doesn't begin checking for updates automatically, click Check For Updates.
3. Wait while your Avast Antivirus checks for application updates.
4. When the update is complete, you will see that Your application is up to date.
5. You may need to restart your PC to complete the update. If prompted, click Restart Now to immediately reboot.

Manage automatic virus definition updates

1. Open your Avast Antivirus and go to ☰ Menu ▸ Settings.
2. Ensure General is selected in the left panel, then click Update.
3. In the virus definitions section, click More options.
4. Tick your preferred option:
   • Automatic update (enabled by default): updates are downloaded and installed automatically on a regular basis. You may need to restart your PC to complete an update. If prompted, click Restart Now to immediately reboot.
   • Ask when an update is available: notifies you when an update is available. Your confirmation is required to complete the update.
   • Manual update (not recommended): updates are not automatically installed and you are not notified when a new update is available.
   • Enable streaming update (enabled by default): downloads micro-updates continuously as new malware is discovered.
   

Manage automatic application updates

1. Open your Avast Antivirus and go to ☰ Menu ▸ Settings.
2. Ensure General is selected in the left panel, then click Update.
3. In the application section, click More options.
4. Tick your preferred option:
   • Automatic update (enabled by default): updates are regularly downloaded and installed. You may need to restart your PC to complete an update. If prompted, click Restart Now to immediately reboot.
   • Ask when update is downloaded: notifies you when updates are downloaded. Your confirmation is required to complete the update.
   • Ask when an update is available: notifies you when updates are available (before downloading). To receive the update, you need to start the download and installation process manually.
   • Manual update (not recommended): updates are not automatically installed and you are not notified when a new update is available.
   

Configure proxy settings

The proxy settings section is for users who connect to the internet through a proxy server. This section allows you to adjust your proxy settings to avoid issues with downloading virus definitions and application updates.

To configure proxy settings for application updates:

1. Open your Avast Antivirus and go to ☰ Menu ▸ Settings.
2. Ensure General is selected in the left panel, then click Update.
3. In the application section, click More options.
4. Tick the box next to Use specific proxy server and type your proxy details into the relevant text box.
   • Type: select HTTP or SOCKS4.
   • Address: type the address of your proxy server.
   • Type of authentication: if the proxy server requires authentication, specify the type and enter the Username and Password.