Dell Latitude 7400 Bios Password

[bitsandbytes206]

Hi I need 8fc8 bios unlocked for Dell latitude 7400 st: 7BZJ8Y2 mobo: EDC40 LA-G871P Rev 1.0 A00
Attached is original dump from UC5 MX25L25673G

[Markus1741]

Hello, your bios is corrupted. Read again.

[bitsandbytes206]

Oh no, that was verified before rewriting. Can I take a dump from different machine but same model?

[Markus1741]

Yes, if you clean the ME region it works.
You can also build a new one.
There is no information such as Windows Key Service Tag stored in your BIOS file.

[abudo]

Hello everyone I need help to remove BIOS password
Dell Latitude 7400
Service tag HN4H353
Board ID LA-G871P
Thank you.

[SMDFlea]

Thread merged.

[rex98]

Hello everyone I need help to remove BIOS password
Dell Latitude 7400
Service tag HN4H353
Board ID LA-G871P
Thank you.

1st boot, press F2, write service tag, disable Absolute, save (Apply changes), restart. 2nd boot press Alt+F to exit manufacturing mode

[Markus1741]

Unlocked file ....

[abudo]

Unlocked file ....

hi I just flashed the BIOS file. I cant turn on the laptop hehehe I will try the other file. I also noticed another 2 winbond chip. should I also post the dump of those 2?

[Markus1741]

[rex98]

hi I just flashed the BIOS file. I cant turn on the laptop hehehe I will try the other file. I also noticed another 2 winbond chip. should I also post the dump of those 2?

our patched are both the same i compared in hex editor. check your solder. or your backup maybe corrupt

[Markus1741]

Hello rex98, thank you for your correction, I have already compared yours and my BIOF file and of course found that our two files are identical.
It was too tedious for me to comment on it because we both don't know what skills the user has, how good their soldering skills are or the like.
I think what most people forget is to do the steps described in the Dell article.

https://www.dell.com/support/kbdoc/e...n-dell-systems

Because the manipulated patch resets everything to the beginning.
So I always do it as described by Dell and have no problems.

[abudo]

our patched are both the same i compared in hex editor. check your solder. or your backup maybe corrupt

thanks rex98 and Markus1741 im going to resolder the chip. Also I deleted the existing BIOS before flashing the patched and unlocked BIOS. Would that affect the process too?

[abudo]

our patched are both the same i compared in hex editor. check your solder. or your backup maybe corrupt

if incase my backup maybe corrupted is there another way to fix the problem? thanks you very much for you reply.

[abudo]

Hello rex98, thank you for your correction, I have already compared yours and my BIOF file and of course found that our two files are identical.
It was too tedious for me to comment on it because we both don't know what skills the user has, how good their soldering skills are or the like.
I think what most people forget is to do the steps described in the Dell article.

https://www.dell.com/support/kbdoc/e...n-dell-systems

Because the manipulated patch resets everything to the beginning.
So I always do it as described by Dell and have no problems.

Thanks for the reply Markus1741 I am 99.99% sure with that solder hehehe but I will still resolder the chip. They are not that hard compared to mobile phone chips. In case my BIOS backup file was corrupted, is there any way to fix the problem? Thanks for you reply.

[Markus1741]

Oops, I once compared your original uploaded file with a file from me without a PW and in my opinion it is defective.
There are too many inconsistencies listed.
The second picture should show yours with PW on the left and mine without PW on the right.
Now you need a new BIOS file, I can build a new one, but from experience it's unlikely that that will solve the problem.
Second choice is a ME region cleaned file, Dell is not that picky.

[abudo]

Oops, I once compared your original uploaded file with a file from me without a PW and in my opinion it is defective.
There are too many inconsistencies listed.
The second picture should show yours with PW on the left and mine without PW on the right.
Now you need a new BIOS file, I can build a new one, but from experience it's unlikely that that will solve the problem.
Second choice is a ME region cleaned file, Dell is not that picky.

can you give me idea on how to aquire those 2 or can you help me get those file. Appreciate your help

[Markus1741]

Hello, this BIOS is mine, I'm pretty sure it didn't have a password.
Try it otherwise we will patch it again.

[abudo]

Hello, this BIOS is mine, I'm pretty sure it didn't have a password.
Try it otherwise we will patch it again.

hi I tried to click verify after flashing and im getting this error (attached). Is this something I need to worry about?

[Markus1741]

Just try NeoProgrammer, your programmer software can't handle the chip.
I would also invest in a T48 or RT809F or RT809H programmer, they come with their own software.

[abudo]

Just try NeoProgrammer, your programmer software can't handle the chip.
I would also invest in a T48 or RT809F or RT809H programmer, they come with their own software.

i dont know how to thank you. Its working now using neoprogrammer. Thank you very much for your time. How can I buy you a beer? hehehe