I started another thread on this problem but I want to move the discussion over here so I will copy paste what I wrote there:
This morning I started my Windows 10 PC and all was normal. Then an authorized Dell Service technician paid a visit to replace the power button LED light which he successfully installed. After that, every time I start or restart my PC I get the same warning, even after removing it to virus chest. So I got on the phone with a Dell support tech for forty minutes and we deleted all the temp files and did a SupportAssist scan, basically cleaning everything up. This was AFTER I did a boot scan with Avast after seeing the first popup. So the Dell tech said it is safe to create an exception for this virus after researching it, and we did that. The boot drive revealed zero threats and yet I got the same popup. I get the same popup after creating the exception. What is going on here?? The Dell rep concluded it is a bug in Avast and was safe to make an exception.