Troubleshooting a PC crash or blue screen error (BSOD)

In some cases, Avast Antivirus products may conflict with third party software installed on your PC, causing Windows to crash, freeze, or show a blue screen error (BSOD). This issue may be due to programs you run manually or background services which run silently when you start Windows.


To determine if the problem is caused by background services, follow these steps:

  1. Reboot your PC and start Windows in safe mode according to the instructions in the following article:
  2. When Windows is running in safe mode, simultaneously press the Win and R keys on your keyboard to open the Run dialog box.
  3. In the Open field, type the command msconfig.exe and click OK to open the System Configuration utility.
  4. Click the General tab and select the Diagnostic startup option to clear all startup programs.
  5. Click the Services tab and tick the checkboxes related to your Avast Antivirus services:
    • Avast Premier or Avast Internet Security: tick Avast Antivirus and Avast Firewall.
    • Avast Pro Antivirus or Avast Free Antivirus: tick Avast Antivirus.
  6. Return to the General tab where Selective startup is now selected, click OK and restart your PC when prompted.
To configure Windows to restart in Normal startup mode, run the System Configuration utility and select Normal startup under the General tab.

If your PC starts working normally again, the problem is due to a conflict with another program or service running silently in the background. Report the issue to Avast Support. For more information, refer to the following article:

  • 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

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