First thing what exact type of computer do you have. Need to have more computer specs. Mother Board type, Ram, Hard Drive, Video Card or Adapter. As with any upgrade did you run the Microsoft Upgrade Advisor. Please check the following link. Upgrading from Windows XP to Windows 7 - Help & How-to - Microsoft Windows
You may have to re-install Win Xp Pro before you can do anything else. Another suggestion is to download Windows Ultimate Boot cd. UBCD for Windows
As with any upgrade from Win XP to Win 7 there are usually a multitiude of issues and some of items in Win 7 will not run on a Win Xp machine.
Again these are all suggestions as someone else may have a better answer than I.
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