I found a tool that will allow you to change you XP key without having to mess with registry or do a clean install. The tool is called sysprep.exe (Windows System Preparation Tool) I found a tool that will allow you to change you XP key without having to mess with registry or do a clean install. The tool is called sysprep.exe (Windows System Preparation Tool). This tool will reset your xp in a way that after you use it and reboot windows will ask you for all user data including the new cdkey. Pretty simple. It will ask to fill out thing as your name, administrator password and cdkey. If you have a diferente and valid key just type it in and you're done. If don't have a valid key and you still use the F key you always can use xpkey.exe (XP Key Recoverer and Discoverer) that will generate a valid key. Don't forget that this tools only work for Windows XP Corporate, not Windows XP Pro or Home Edition.
Here are links where you can hook up with these tools:
SYSTEM PREPARATION TOOL v2XP Key Recoverer and Discoverer v5.12