Weirdest thing is, i was running the insider version of the anniversary update (sr-version) and that gave me no problems at all...
But after leaving the pc for an hour, microsoft thought it would be nice to install the anniversary update and added the complimentary reboot, which bsod'd (multiple times, but is was not able to autocorrect/repair it).
Not knowing it was a compatibility issue windows10anni/avast, after two hours of trying to 'systemrestore' my system to relative health, i reverted to a clean install (not so bad after a year of tweaking) only to be greeted with a bsod on install of avast free.... bang!
That made it clear (at least part of) the issue was with avast...
So until avast and microsoft agree on what where etc. i will keep extra alert while using defender.
Pity, been using avast for many years now, only one real hickup for me (besides this one, that is).