Let's try a manual approach here.
Are you familiar with using Regedit? If you are not check out this
tutorial on how to start it.
Then navigate and delete the following registry entries:
HKEY_CURRENT_USER\Software\Ask.com
HKEY_LOCAL_MACHINE\SOFTWARE\AskToolbar
HKEY_USERS\S-1-5-21-4155921847-2839181805-2297933737-1001\Software\Ask.com
Select one of the above entries and delete it. See attached image for reference. When you selected a key as seen in the picture push the Delete button and confirm or right click and choose Delete and confirm.
When you are not experienced with working with the registry make a System Restore point before removing these keys.
Let us know if this of help for you.