After having such a great time at Build I felt it was time to upgrade my work laptop to Windows 8.  Previously, however, I had Windows 7 Ultimate and when I tried to upgrade to Windows 8 Enterprise the installer told me I could not do so: “Windows 7 Ultimate cannot be upgraded to Windows 8 Enterprise.”  The natural path is to upgrade to Windows 8 Pro but I specifically wanted Enterprise since that was what we have at work and for the ability to side-load Windows Store apps (though maybe Pro can do this as well).

Anyway, just by luck I happened upon a post about a very similar problem going from Vista to Windows 7 Enterprise … same issue.  The fix?  Totally stupid … really.

1. Close the Windows 8 installer if you have it open and
2. Launch RegEdit to edit the registry
3. Find the following branch: HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\Current Version
4. Edit the following keys:
   1. EditionId – Change from “Ultimate” to “Enterprise”
   2. ProductName – Change from “Windows 7 Ultimate” to “Windows 7 Enterprise”

Now the in-place upgrade will run just fine.