THIS IS ONLY FOR PEOPLE ALREADY UNLOCKED BEFORE THIS FIX WAS DISCOVERED. IF YOU HAVEN'T UNLOCKED GO HERE.
Thanks to glossywhite and John W for figuring this out!
I CAN'T TAKE ANY RESPONSIBILITY FOR BRICKS ETC. BUT I WILL TRY MY BEST TO HELP YOU
You need to have stock recovery at the start of this tutorial. You can do it in the same way as you unlocked
- You should already have QPST installed
- Download a Hex Editor for Windows - anyone is fine - Google "Hex Editor" and install it
- Put your phone into FTM mode - the same way as for unlocking
- Go to your start menu, QPST and then run Software Download
- Go to "Backup" tab and backup your nvitems
- Open your hex editor and open the *.qcn file that you saved with QPST
- Search for "11 22 33 44 55 66" with your hex editor
- Replace this with the MAC address you wrote down when you unlocked.
- Save the file
- Go back to "Software Download" and go to restore and choose to restore the saved *.qcn
If you're stuck on the editing bit have a look at this video made by Glossywhite: