AVG Performance Unlimited - installation failure error on XP

Hello John,
I'm sorry to hear that you're experiencing issue with AVG Performance(AVG PC Tuneup) installation on your Windows xp computer. The error you received is mean that you might have any previous AVG PC Tuneup traces or you have installed any other system performance program. I have sent you an email, please follow the email instruction to connect with us remotely. We will check with your installed AVG program and we will assist you further.
Best regards,
Alok.

Trying to install AVG Performance Unlimited, I keep getting error 0xc007001d (on Windows 5.1.2600/XPPro SP3 POS ready fully patched).  Anyone know what this error code means and what needs to be done to get round it?  I have used TuneUp Utilities sucessfully on this machine for several years beforehand with no problems.    I have tried running the AVG removal tool several times.
It may be related, but if instead I try to install AVG Basic AV for XP, I get the error "avgsetupx.exe has had a problem and needs to close".  What is wrong now that upsets both these installations?

Hello John,
I'm sorry to hear that you're experiencing issue with AVG Performance(AVG PC Tuneup) installation on your Windows xp computer. The error you received is mean that you might have any previous AVG PC Tuneup traces or you have installed any other system performance program. I have sent you an email, please follow the email instruction to connect with us remotely. We will check with your installed AVG program and we will assist you further.
Best regards,
Alok.