Did you do an upgrade over a valid copy of WIn7/Win8.1 first?? You will need to do that first in order to perform a clean instillation or you will not be able to activate Win10.
And no.. your not activate at this time.
A few things to try. Make sure you have the Insider Preview key written down you used to install it with. Open an elevated command prompt ("run as administrator" command prompt).
Enter slmgr /upk - that will remove the insider product key and cause Windows to deactivate.
Enter slmgr /ato - that will cause Windows to attempt to activate without a product key, probably won't work but worth a try.
If that does work - enter slmgr /xpr - if it says permanently activated you are good to go. STOP and enjoy Windows 10!
If that does not work - enter slmgr /ipk VK7JG-NPHTM-C97JM-9MPGT-3V66T
That will put the generic upgrade product key in.
Enter slmgr /ato - again probably won't work, but worth a try. If it does work, then slmgr /xpr - if it says permanently activated, you are good to go!
If none of that works then:
slmgr /upk, slmgr /ipk [insert insider preview key here], slmgr /ato - to get back to your temporary activation.
Either wait to see if a new insider build is available for Jan, 2016 or go back and install a Windows 7, 8 or 8.1 and upgrade to free Windows 10 from that.
Yes, you are correct - I did use the INsider key to activate my Win10 install ofbuild 10240.
And no, I did not do an upgrade of my Win7.1 system. Instead I downloaded the 10240 ISO file and did a clean install on a brand new SSD boot drive. Then I simply swapped out my old Win7.1 drive for the new one.
My understanding was that this was the correct way to get a legit WIn10 clean install. Did I miss something? What should I do prior to Jan 2016 to keep my Win10 activated?
That is a KMS 6 month activation notice and has nothing to do with Insiders evaluation period.
Google -T83GX (it's a volume license key), the winaero site has full details.