I am unable to activate Windows 10 Technical Preview Enterprise build 9860. I receive Error: 0x8004FC12. I have tried one fix of manually entering the key and manually activating. Below is the result.

C:\WINDOWS\system32>cscript slmgr.vbs -ipk PBHCJ-Q2NYD-2PX34-T2TD6-233PK
Microsoft (R) Windows Script Host Version 5.8
Copyright (C) Microsoft Corporation. All rights reserved.

Installed product key PBHCJ-Q2NYD-2PX34-T2TD6-233PK successfully.


C:\WINDOWS\system32>cscript slmgr.vbs -ato
Microsoft (R) Windows Script Host Version 5.8
Copyright (C) Microsoft Corporation. All rights reserved.

Activating Windows(R), Enterprise edition (72e02447-a7bc-462c-9c3d-e5c919a5140a)
 ...
Error: 0x8004FC12 On a computer running Microsoft Windows non-core edition, run
'slui.exe 0x2a 0x8004FC12' to display the error text.

Any help would be appreciated.

Me too!! Exactly the same errors..

So after investing another 30 mins doing packet captures, removing and re-adding keys with slmgr etc.. I thought I'd try phone activation using "slui 4".  

All worked fine and now activated.. Not sure why it wasn't working with online activation.

Excellent - telephone activation worked for me! Thanks!

After installing the Windows Updates that were available and restarting, my computer activated.

i m activated on windows 10 developer preview build 9860, when i was downloading windows 10 technical preview 9840 they gave me key on that site. i used that key and now i m activated...

I have solve the same error with a simple two steps process:

Start services.msc

Restart Windows Update

Restart Windows Installer

Thanks

Mark