I originally had Avast!4 Home.
I got a virus warning and tried to run the prog.
It would not run, I don't know why.
I removed it via Control Panel/Add Remove.
I downloaded and paid for Avast!v.4.6 Professional.
I registered, recieved and entered the Release Liscense Number.
Currently the program opens and throws up the error message 42000=unknown error.
My operating system is XP Professional
Hope that helps,
Cheers