Installation Error Code 0xE001F94E

On my Windows XP pc I have uninstalled Free AVG and now while trying to reinstall it I receive the following message "Update cannot proceed due to source/target version mismatch.
Error code: 0xE001F94E".
The Add/Remove part of the Control Panel shows that AVG is not there.
I'm installing the latest version of free AVG, I've restarted the PC numerous times but I'm still getting the same message, any ideas anyone?

Rob, Are you using Win XP Service Pack SP3?.
AVG Guru

Rob, Are you using Win XP Service Pack SP3?.
AVG Guru