I still have a desktop running windows XP that my parents refuse to upgrade, partially due to a piece of software licensed per computer that costs >300$. Thankfully chrome no longer opens half the websites so they are limited on the web side at least. 14+ years of service, the only times it blue screemed were due to hardware breaking down. Rock solid.
No I'm not touching it with a 10 feet pole. Besides the fact that I would need new hardware for that( it's a core 2 duo system) which they are unwilling to fork the money for, anything that happens with it in the future will be my fault.
No I'm not able to reinstall. I am also not willing to deal with tech support. If and when it dies I'll just order a dell for them and they can sort the software issue themselves.
