Weird results. I upgraded a Windows 8.1 Professional Dell 131L laptop which had a KMS product key from 2.5.1. When I upgraded to Windows 10 with 10261 and went thru the TH1 Windows 10 updates the laptop was configured for Windows 10. The weird situation was the laptop was looking for the new activation and it didn’t like any of the keys either from Windows 8 or Windows 10. The error message I kept getting was in didn’t like the KMS activation from 2.5.1. So I brought up the 2.5.1 KMS and did a “REARM” command which forced the laptop to be restarted. If I run my AID64 Engineering software and ckeck the product key for the 131L laptop it shows a valid key. So the weird thing about this is when I restarted my 131L with all the current updates from Windows 10, and doing a REARM, I now have activated Windows 10 laptop. Any comments on what happened?