Help installing 11.15 with avast and false positive virus detect

[HomerJ]

I know the 11.15 virus detection is a false positive.  However, I'm having issues installing LB with Avast installed.

When I instsll, I get the false detect

Then I create the exception

But then the instatller gives me this error:

 

I click 'try again' over and over, and it never works.   I'm stuck.