Microsoft will not let you upgrade from consumer Vista versions to Windows 7 by default. To get around this you can modify some registry keys to make the Windows 7 Enterprise disc think it is upgrading Windows Vista Business.

Here’s how to get past this message:

Go to, Start, Run: and type: regedit.exe
Go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion
Change the Key “ProductName” from “Windows Vista Ultimate” to “Windows Vista Enterprise”
Change the Key “EditionID” from “Ultimate” to “Enterprise”

Now restart the Windows 7 upgrade. You should now be able to upgrade!