You probably need to do a clean install...
Download and save the avast uninstall tool
Download and save your choice...FreeProAvast Internet SecurityPremier
Run the uninstaller from above. You will be directed to reboot into safe mode...click "yes".
Install choice from above. Use the "custom" install. You may need to either de-select the "browser protection" or disable the "avast online security" add-on in your browser(s).
Reboot and either register or insert license.
Dell Inspiron, Win7x64 SP1, Comodo Firewall 5.12 w/D+, MalwareBytes Free 2.1--HP Envy Win8.1x64, MalwareBytes Premium 2.1--Both systems Avast Free v2015.10.2,2218, Super Anti-Spyware, Spyware Blaster, MCShield, Unchecky, Firefox (latest build), Google Chrome (latest build) and, various browser security tools.
When you do something, do it with a purpose and do it on purpose.