Tomb Raider Demo Help

I have downloaded the demo from Gamespot.  When trying to launch the program, get message: "TombRaiderAnniversary_Demo.exe is not a valid win32 application".  Any suggestions on how to run this demo?

Thank you in advance:) 

1. File is corrupt, bad, or missing.
2. File is not designed for your version of Windows.
3. File is a virus, worm, or other malware file.
4. Hardware incompatibility.

got that off the internet. Try checking for viruses, make sure you meet the minimum requirements, de frag your hard drive (probably won't help, but it's good practice.) re-downlaod.

 I downloaded Anniversary frome GameSpot as well, it worked great on my WinXP. and I think this Tomb Raider is pretty good as the way it shouldve been.....I liked it so far.