Sorry to hear that, though I 100% understand your reasons. If I can have my 2 cents worth though I would urge you to think very carefully. I have used most AntiVirus software over the years and I feel obliged to say that although Avast has its problems, so do they all. The Avast team though, in my experience are the fastest to respond and quickest to fix issues I have ever come across. I suspect they can't answer your concerns because they can't replicate your issue with any degree of confidence. I assume you are backing up over a network? I don't recall you saying exactly what your problem was.