SupportScam:JS/TechBrolo.F

[Hugo156]

Hello,
This morning my PC has been infected by a trojan named SupportScam:JS/TechBrolo.F. Windows Defender has detected this threat however Avast did not. In fact, Windows Defender said that "C:\Windows\Temp\_avast_\nsfsp00001943.tmp" has been affected by this threat. Moreover, each time I start my computer, the agent suspicious actions is disabled and each time I make a smart scan, my computer crashes and I have to restart it. According to Windows Defender, this threat has been eliminated but my computer is extremely slower now. So what should I do ? Should I re-install Avast ?

[DavidR]

Well considering that temp location is where avast scans content.

It would appear to be one of a few things:
1.  Why is Windows Defender scanning that location, as in theory it shouldn't be running as an on access scanner.  Potential conflict between two AVs. See questions below.  If not clear then avast could be beung blocked from clearing it by defender alerting.
2.  That location when avast finishes scans should be cleared and the only file remaining would be AvLock.txt (see attached image).
3.  A possible false positive Windows Defender rather than a missed detection by avast

Question
What OS are you using ?
What version of avast are you using ?
Is Avast running in passive mode and or is Defender active, rather than disabled (as it should when you install a resident AV) ?

EDIT: Oops, forgot the attachment.