Can Windows Defender and Avast run at the Same Time?
Windows Defender will automatically turn off if it detects any third-party anti-virus software. You don’t have to use both Windows Defender and Avast at the same time on your system. And processing wise it will put an unwanted load on your system and maybe your system will work very slow.
If you still run windows defender and avast at the same time then it will cause a conflict. Therefore to prevent conflicts windows defender turn off when it detects any third-party anti-virus.
When your Windows defender is on it will notify you whenever any unwanted software, malware, or spyware tries to install or run automatically.
I would prefer Avira or Avast instead of windows defender. Windows defender consumes many system resources and it also has poor detection.