McAfee, LLC Did not protect computer San Jose California

I paid for upgraded computer protection at a cost of $89.99.  Shortly after, my computer started doing all kind of weird things (ie changing & deleting documents). 

I worked with it trying to correct things that messed up for months believing it couldn't be a virus because I had supposedly purchased good virus protection. 

Finally, I took it to Best Buy, where they found and deleted 14 viruses at a cost to me of $199.99.  I have notified McAfee of the problem and asked for a refund.  However, I haven't heard back from them.