[crazygamelover]

did you have to format the drive when you first started the install process?
If so you may not be able to go back before the prob and correct it.
What are the specs on the PC? (processor, mem, hdd)
You can try removing all of the devices in the computer except for the ones you need to perform the install. (rom drive) Then attempt the install again. When you first get started, you should be able to reformat the drive and wipe clean any previous install attempts and start fresh. Hopefully there is a device or 2 that is conflicting and by removing them will allow you to proceed with the install. Once (If) you get through the install successfully, you can put the devices back in and proceed to do the setup on them one by one. I know this sounds like a pain but if your prob is a conflicting device, this may be the only way to tell. You would think that if the home edition was previously installed, you would have no probs with the Pro edition. Very odd!