Software install not recognized, I think

[Maggotry]

Hi guys. A problem just started on my son's PC. No idea why it started, but here's what's happening:

When my son inserts a CD for one of his games, the installer program launches and tries to reinstall the software. Every one of his games are affected by this - UT3, Lego Star Wars, Battle for Middle-earth, etc. The computer acts like it has no idea those titles are already installed.

Any idea what could cause such a thing or any ideas on how to fix it? I assume the problem lies somewhere in the OS.

Thanks

 

[nerp]

Do you see the game in the start menu? Try launching it from there first. What happens if you try loading a game that way?

 

[Maggotry]

All the game icons are still on the desktop and the entries are still there in the Start Menu.

If I start the game using the icon on the desktop, it asks if I want to remove the application, similar dialog you'd see if you used the "Add/Remove Programs" application.

Ultimately, I can cancel out of all the dialog and get the game to start. When the game starts, it asks for the CD Key as if it had never been installed.

I launched UT3 3 times. It asked for the CD Key every time.

I should have stated - Windows XP SP3.