Getting "Engine cannot launch" message with Avast

[keithh]

I cannot delete/remove Avast. Whenever I try to run it I get the above message with a Terminate button and when I click on the button Avast disappears but every email comes up with a similar message. No one is answering my cry for help on the Avast forum so I wondered if anyone here has had a similar problem and can help me remove it. It was suggested that something is in my Launchd plist . What is that and how do I check it?