Windows 10 has already had one big “upgrade” released, version 1511 in November 2015. Another one is coming soon in Summer 2016. After you run these updates to Windows 10, you can no longer use the Sysprep tool because it considers these to be full OS upgrades. The error you get is “Sysprep was not able to validate your windows installation.” Fortunately a trick from Windows 7 and 8 days still works to get around this limitation. I found that you only have to do the first 2 steps from the source, so I only reproduced those here.
Below is the method that I found to work perfectly.
Remove thisÂ KEYÂ from the Registry:
Remove this REG_DWORDÂ from the Registry:
After your operating system is activated re-run SysPrep and it will work!