Manage threat responses

Before scheduling and running a Boot-Time Scan, you need to specify automatic actions for how Boot-Time Scan handles detected threats. If you disable automatic actions, you are prompted during the Boot-Time Scan to manually select an action for each detected threat.

To specify how Boot-Time Scan responds to detected threats:

1. Open Avast Antivirus, then select Protection ▸ Virus Scans.
2. Click Settings (the gear icon) on the right side of the screen.
3. Select the Boot-Time Scan tab.
4. Scroll down to Perform automatic actions during this scan. Tick this option to enable automatic actions. If you untick this option, Avast asks you what to do each time a threat is detected during the Boot-Time Scan.
5. If you enabled automatic actions in the previous step, select your preferred automatic action:
   • Fix automatically (recommended): Avast Antivirus attempts to repair the file. If unsuccessful, it moves the file to Quarantine or deletes the file if neither action is successful.
   • Move to Quarantine: Avast Antivirus sends the file to Quarantine.
   • Delete: Avast Antivirus permanently removes the file from your PC.
   

When you run Boot-Time Scan, Avast Antivirus scans your system for threats according to your preferences.

After specifying how Boot-Time Scan will respond to detected threats, follow the instructions below to schedule it:

1. Open Avast Antivirus, then select Protection ▸ Virus Scans.
2. Under Boot-Time Scan click Open now.
3. Click Install definitions, then click Run on next PC startup to run the scan during the next system restart.
   When you click Install definitions on the Boot-Time Scan screen, Avast Antivirus downloads all virus definitions from a cloud database. If you skip installing specialized definitions, Boot-Time Scan scans your PC based only on the last virus definitions that were downloaded. If Install definitions is not displayed on the Boot-Time Scan screen, your virus definitions are up to date.
   
4. Restart your PC. When the system restarts, a Boot-Time Scan progress screen appears. The scan usually takes several minutes, but the duration varies depending on the speed of your system and the number of files being scanned. To skip the scan, press the Esc key on your keyboard.
5. For any detected threat, Avast Antivirus applies the action specified in your application settings. If you disabled automatic actions and threats are detected, tick the boxes next to relevant threats and select Resolve all or Resolve selected.

When the scan is complete, Windows continues booting up.

Adjust scan settings

To further customize the settings for Boot-Time Scan:

1. Open Avast Antivirus, then select Protection ▸ Virus Scans.
2. Click Settings (the gear icon) on the right side of the screen.
3. Select the Boot-Time Scan tab.
4. Define the following settings for your next Boot-Time Scan:
   1. Sensitivity: Use the slider to indicate your preferred level of heuristic sensitivity. Heuristics enable Avast Antivirus to detect unknown malware by analyzing code for commands that may indicate malicious intent.
   2. Notify me about potentially unwanted programs: Ensure this box is ticked if you want Boot-Time Scan to look for programs that are stealthily downloaded with other programs and typically perform unwanted activity.
   3. Scan for Tools: Choose to detect or ignore "Tools" like coin miners and key generators.
   4. Unpack archive files: Ensure this box is ticked if you want Avast Antivirus to unpack compressed files during the scan.
   5. Parts of your PC to scan: Select All hard disks or System drive to specify which data space you want the scan to analyze.
   6. Auto start programs: Allows Avast Antivirus to scan programs that automatically start when you turn on your computer.
   7. Perform automatic actions during this scan: Configure automatic actions for any threats detected by Boot-Time Scan.
   

For more information about scans in Avast Antivirus, refer to the following article:

• Scanning your PC for viruses with Avast Antivirus