Here's one for you....
I have tried running a full system scan with Norton 360 several times now and it always hangs up somewhere before completion. I have reloaded Norton 360, upgraded to v22 and numerous reboots all with the same results. I have even let Norton run for 3-1/2 days and it doesn't complete.
As a check I downloaded a trial version of AVG and the same thing happens...it gets to a certain point and then does not proceed any further. Getting version updates doesn't help either.
I have run Norton Power Eraser and Malwarebytes Premium and they don't help. I fact, neither of then =m found more than a few tracking cookies.
Suggestions? (no, I am not going to do a complete clean reinstall of Windows 8.1 64 bit, which is my OS)).