Avast 6.0.1367 quit working

I have had avast free for 10 years. 3 days ago it stopped working. It will not FIX nor will it START back up. I have gone into Windows “services” and tried to manually start it. It says it starts and then stops. Avast no longer appears in the programs list in CONTROL PANEL. It will not delete from C:\Programs. I have downloaded a new copy of the free version and also the paid version but neither will install. I wrote to avast on Tuesday and they still have not replied. I am using windows 7 64 bit
I scanned using Malwarebytes and also security essentials. No problems

if you already have MSE then you sould not install avast…or vice versa
never install more then one antivirus…so you need to uninstall one before installing a new
malwarebytes you can keep

it is also recomended to run a removal tool to clear any leftover files that may conflict

http://singularlabs.com/uninstallers/security-software/