I spent much of yesterday trying to upgrade Windows Vista x64 on both my MacBook and my Hackintosh. But on both systems I received errors during the Windows Setup process. After a day of trial and error, Googling and experimenting I have finally gotten Vista upgraded to Windows 7 on both systems. Incidentally, the solution was quite simple for both computers. Even though I was upgrading Windows Vista Home Premium this should help anyone with Business or Ultimate as well. The errors I was receiving is that Windows Setup either couldn't create the necessary installation folder, or I was being told I didn't have enough disk space. If you have a Mac and are using Boot Camp to load Windows you may be receiving one of these errors. If this is the case simply uninstall Boot Camp. After uninstalling you'll be told to reboot. Try upgrading to Windows 7 again. It should run. After Windows 7 installs simply re-install Book Camp. This is how I got Windows Vista upgraded to Windows 7 on my MacBook. For those with Hackintosh systems you probably have your OS X drive as the primary boot drive so it can load a bootloader. If you are receiving an error during Windows Setup go into your BIOS and change the primary boot drive to your Windows drive thus bypassing the bootloader. Once Windows boots you should be able to run Windows Setup. After Windows 7 is installed just change the primary boot drive in your BIOS back to your OS X drive. Hope this helps.