Keyboard keys not working in WInXP

[hardworkingPhD]

I have installed a guest WinXP VM on my MAC OSX. Everything works great . . . except I can't register Windows. The only time my keyboard keys seem to be messed up is in the "register windows" screen. When I start to enter the register code, the "Z", which I need, doesn't work. A few other keys also don't work, but the "z" is the only one I need for the code that isn't working. Any suggestions?