McAfee Sabotaged my computer Internet

I purchased McAfee virus protection via internet and the technician who assisted with the download of the protection stated that he need to take control of my computer to get the virus installed correctly.  After he was done the protection was installed but my complete Microsoft Office Suite was missing along with other files and programs that were previously on my computer and in good working order.  I have called them many times trying to get this matter resolved, but each time I am told this is not their problem.  I asked them what happened to my files and why were they removed, but I still couldn't get them to see that my files had been taken off.  I gave them the name of the tech who did this, and they told me they have no such person on their staff.  After five tries and getting the run around each time, I stopped corresponding.  I found out later that my neice suffered the same loss to her computer when she bought MacAfee also.