invalid license number after reinstall 4.8 Home

Hi,
I had to reinstall avast! today and after a clean removal using the tool provided, I was able to reinstall it again. Unfortunately I cannot make it work due to the “invalid license number!” error. I registered, and I’ve got new license key. The old license is not working either. I have XP Home - SP3, and I’m not running any other antivirus or antimalware, etc…
Have any ideea what could be and how can be fixed?
Thanks

that was happen with me when i restore a backup of system stat"*.bkf"and the solution was to uninstall avast completely by avst remover tool:www.avast.com/eng/avast-uninstall-utility.htm
then install avast that will work if you dont have viruses that can kill av.so go here if the first way dont work:
http://forum.avast.com/index.php?topic=50106.0

Thanks superhacker. I told you that I used the tool to remove avast! and I installed back properly. I have also new license number. Anyway I’ll try one more time to remove it and reinstall it back these days. I’ll post back the results.
Thanks again