Need some help with answering a question on the Russian site

Ouch! Sounds like the firmware was in the middle of being updated and in the process the S/N got messed up as the system was forced to shutdown causing an incomplete write operation.

I haven’t done any of the newer retina series or anything OS-X newer than Mountain Lion which is the last version that you could poke the value in via hex. This required taking the EFI chip out and using a EEROM burner export the file image, then edit it and then reload back into the chip.

Apple made a lot of changes in the newer firmware releases I don’t think you can alter now as it has a serpentine key so any alteration invalidates it. This also prevents any firmware update as well (locked in the this bad state).

Apple would be the only ones who could fix this, but as we know they don’t do any logic board repairs at the depots only full replacements.