Marios, Have a look @ this article (https://support.avg.com/SupportArticleView?urlname=How-to-renew-or-upgrade-your-AVG-license).
AVG Guru
I need instructions how to pay using this windows 7 computer for the renewal of a product on a different XP computer. I do not like to let my credit card appear on a less protected computer like an XP computer.
Marios, Have a look @ this article (https://support.avg.com/SupportArticleView?urlname=How-to-renew-or-upgrade-your-AVG-license).
AVG Guru