Following this thread as I am experiencing excatly the same. Same popup each time I open the computer, - avast says its blocked - all is safe.
From what I read in this post it seems that the things you have tried have really had no effect, is that correct understood ?

Just checking, cause no need to go through the same process if it doesnt help anything …

I didnt initially think it was ‘on my computer’ but more an attempt from outside to try to ‘get into my computer’ but that this had been blocked ?

(just adding, I am no expert on computers, just a simple user with avast)