Can't Open .XPS Please Help?

I was typing my essay for school on microsoft office 2003. I asked my mother if she could read it over and tell me what she thought of it and so she could give me some feedback on what to improve. I hadn't saved it in a while, and so she asked if I wanted to save the document, and I of course said "Sure." But before she did that, she wanted to print it out. So she entered the printing pane, and it wouldn't let her print it unless she saved it anyway, so she did, but apparently, the original file, which was a normal and easy to open file, was replaced with an updated .XPS file. I can't open it now. Can someone PLEASE tell me what programs to download to open this file extension? I REALLY don't want to start over my whole essay because of one stupid mistake!