I was just reading some posts on the forum and this box popped up…AvastUIEXE…Application Error…Red X …The instruction at 0x773Ae3b…Referenced Memory 0x7cbd1dc. The memory could not be read. Click okay to terminate the program. Wasn’t able to get a screen shot. What does this mean? A few seconds later the Avast Update popped up saying it had been updated.
I did click okay to terminate the program but still stayed on the forum.
Hi: I’ve experienced similar glitches over the years. :-
Not sure the cause, but if all seems normal and Avast is running with most recent VPS update then I would say you should be good.
Just, note any abnormalities and provide screenshot and any error messages (if you get any).
All should be good. 
Personally I would just reboot and unless it became a regular occurrence I wouldn’t even investigate it.
Memory locations can change, especially if you are short of memory (?) then some memory sectors may have been moved out to the swapfile (pagefile.sys) so it is possible to get these kind of errors.