This is on a Windows Vista computer. Whenever my friend tries to open Microsoft word it doesn't open, but under processes it is "running". Any suggestions?

Edit: In the title it's "not on my computer" not "now on my computer"

If your friend has the installation disc for Office, insert it, and proceed to do an install. It should bring up a screen with an option to do a repair. Try that.

If they don't have a disc how will they fix it? I have a feeling my friend doesn't have the disc since usually Microsoft Vista comes with Microsoft word.

If they have a Repair disc for the system, it's possible that initiating Word (or Microsoft Office) in the Add/Remove Programs may bring up the Repair option and ask for the disc. Browsing the disc may also find a folder that has the Word (or Office) installation in it. A setup.exe in that folder should start it up.