Upgrading to Froyo – AT&T Captivate – Mini Kies “unregistered device” error
I know there are many people who are getting this error when trying to upgrade to Froyo firmware using Samsung KIES. I was gettting this error and after 2 hours of efforts, I could finally figure out what was wrong and I could flash the firmware!
So what was wrong?
1. If u have installed custom roms (Honeycomb) , then chances are your IMEI number was overwritten.
2. Also chances are your product code is also overwritten
To get these back, Refer to this post : http://forum.xda-developers.com/showthread.php?t=881162
Once it is done, you product code should now be i897ZKAATT
If its not, go back and see what you missed. Dont continue. It will not work.
After this, REVERT BACK TO STOCK -> factory reset -> THIS IS IMPORTANT
Lastly, after your phone is reset , connect back to KIES and the upgrade should successfully complete now!