Originally Posted by diablo009
Take to some repair shops that write to NAND with your original IMEI. No offense, but no person in the right sense of mind would give you their EFS or IMEI. Be warned... it is ILLEGAL to change IMEIs.
Good advice, but the last part is wrong. It may
be illegal to change an IMEI.. that varies depending on where you are located and in some cases why you are changing it. It is not illegal in many jurisdictions and in fact factory authorized service dealers change IMEIs all the time. AFAIK it is not illegal anywhere to restore your original IMEI, which is what you should be striving to do anyway.
However as you might appreciate, threads about IMEI modification are emphatically discouraged and not infrequently locked on XDA due to abuse. Or the potential for the same. It's not a subject that we should be discussing at length other than to briefly suggest that an OP restore a backup if possible. Or seek a reputable repair shop otherwise.
Anyway, glad that the OP managed to resurrect his phone (even with the annoying thread title). Sounds like he had a backup (in Kies) that he didn't realize. And therein is the most important message - everyone should have a full backup of their phone, including the EFS.