mbp 2012 retina 13.3 efi locked please help

is possible to remove block and insert another serial w8043027agw , i have tryed with a new file download in the section and insert the serial number,
correct the dimension of file maybe the macbook not go on. with original work maybe locked ....
Thanks for the help

model 2557

Intro. October 23, 2012 Disc. October 22, 2013*
Order MD212LL/A* Model A1425 (EMC 2557)
Family Retina Late 2012 ID MacBookPro10,2
RAM 8 GB* VRAM 768 MB*
Storage 128 GB, 256 GB SSD Optical None*

I think the reason why you're having this issue with the file size is because when you enter your s/n of W8043027AGW you're replacing a 12 digit number with an 11 digit number causing the file size to change. Adding a null character should fix this. I've added your s/n, removed the lock, added null and the file size remained where it's suppose to be. Give it a try and report back please.

Also make sure to clear NVRAM and boot to external drive and reinstall OSX.

yes please let us know how you get on.

thanks for your help coronaflyest

NP, I did my first flash today and it went incredibly smooth with all the info on this site. I will be giving back to the community. There is great support on this site.

thanks so much i try now and i reply thanks

Good Work perfectly work witouth problem this forum is the number one good jobs

I'm glad it work.