Hi, Folks: I have a Dell Inspiron 3847 with oem Windows 8.1 Pro on it. When I upgrade to Windows 10 RTM, I found I lose the OEM license. the "OEM" disappear from the end of the Product ID. With Slmgr /dlv on command prompt, it said it is a retail version. Aren't we supposed to get the a oem from a oem?