Can any one tell me why I can not install this game

not with no information.

do you have administrator privilege on the PC you are installing the game to?

do you meet the system requirements?

We need far more information than that to help you. What Operating System are you using, what error messages are you getting if any, etc. I can offer a couple of guesses about your problem though.

If you're on Vista and selecting "Install" from the Autoplay menu doesn't do anything, follow these instructions.

If the installer is freezing on about 95% complete, just leave it there for as long as you can (it can take ages once it gets to 95%, even up to 20 minutes I've heard. It took so long when I installed that I was getting seriously worried that there was a problem with the game or my computer, but it did complete eventually).

If it's gotten to 95% and is absolutely not installing, follow these instructions.

If you're having a different problem to the above, please post back with specific details of your problem