I came across a problem when installing Windows 7 to my Mac using Bootcamp. I purchased my copy of Windows 7 when I had my older Windows PC meaning I was eligible for the upgrade pricing. Using a Mac, however meant I couldn’t use the upgrade disc. Seeing as I don’t use my Windows PC anymore (it’s since been wiped and Ubuntu installed) I think I’m entitled to use the software I purchased on my Mac! The installation runs fine, with no issues, except when you enter your Product Key in. Windows gives you a nice error during install saying the Key is Invalid. It still allows you to install Windows 7, but you must reactivate within 3 days.
The quickest, and easiest way to activate Windows 7 using your own Product Key is to do the following:
1- Open up regedit (Click the Start Orb, type regedit and press enter)
2- Navigate to HKEY_LOCAL_MACHINE/Software/Microsoft/Windows/CurrentVersion/Setup/OOBE/
3- On the right hand side, double click MediaBootInstall and change the value to 0 (from 1)
4- Close regedit, and start a command prompt as an administrator
5- Enter slmgr /rearm and wait for a message box telling you the command completed successfully
6- Reboot your Mac
7- Click Start, and type Activate Windows
8- Enter your Product Key and click OK.
Easy as pie! Special Thanks to Justin Kerr of the MaximumPC blog for the information. Their site has pictures that can also be followed!