HM77 Mobo Bios lock removal did not work out

Hi Gurus,

I am approaching you for a thing which may be a simple thought and will take days to figure out for me.

I am writing the modded BIOS to chips by CH341A programmer every time and am desperately trying since a week to be able to perform BIOS modifications through FPT.

I have removed the Descriptor lock by using FITC.

Next, I did two changes to PchBiosWriteProtect suggested by Coderush Changing 0xFE to 0xFF and Changing 0x20 to 0x00. But, no luck still getting the error "Error 28: Protected Range Registers are currently set by BIOS, preventing flash access. Please contact the target system BIOS vendor for an option to disable Protected Range Registers." when I try to execute 1. fptw64 -d dump.bin 2. fptw64 -f dump.bin.

Next, I did replace the test statements with 4831C0 in PCHinitDXE at two places at BPL register comparision 40 84 28 -> 48 31 C0 and at BiosLock comparision F6 00 10 -> 48 31 C0. But, still no Luck.

Please let me know if you want the bios dump to be sent you if you want to have a look at. I even removed CMOS battery and reset NVRAM.

System BIOS version : A14
System Model : Inspiron 15R N5520
Chipset :- HM77 Mobile
CPU: i7-3632Qm

Can you please tell me if I am doing something wrong.

Thanks in Adavance for your suggestions/inputs.

Pavan.

Hello Gurus,

Any hint/suggestions highly appreciated.

Further patched my BIOS with UEFIPatch and disabled Intel Anti-Theft Service still no luck getting the same error.

Thanks & Regards,
Pavan