I put the the modified bios biosm.bin + bios.s12 into a usb flash stick and make a recovery. A strange message appears for the first time for me “flashing boot block” and a loading screen appears below, Then the loading suddenly stopped in the middle and the laptop restarts again. after restart the laptop boots normally. then i go to the original F16 flash folder and run insydefladh.exe. The update button return be active again do not how. After i clicked update i got a new warning message that you are trying to flash older bios F16 ok?. I clicked ok to proceed, the bios flashed back to F16 normally. Thank you again for all of your time.

Thank you

Hello everyone,
I am having the same problem of @Zeca123 but a different hp laptop (15-ah150na); I want to downgrade my bios because the last update badly messed the dsdt. I tried to follow the procedure @Lost_N_BIOS suggested in post #13 and modified the bios version, but I keep getting the same "signature not found" error. Since I am not very familiar with insyde bios modification, could you explain me, or point me to where I learn, how to modify the bios version without changing the checksum of the file?

Mod is not possible with RSA Signed BIOS. You're only option is to dump the BIOS with flash programmer and modify that, and that may also fail to boot.
You certainly can't use anything posted in previous replies here, since you do not have the same laptop!!!

I can make you mod BIOS like I did for Zeca123, but he was lucky it didn't brick, and recovered, you may not get so lucky so maybe get CH341A programmer + SOIC8 test clip with cable first.

You should try method linked last at post #13 while you wait on programmer to arrive.

Thanks, for you reply. For some reason I don't know HP emergency recovery doesn't work on my laptop. Probably programmer and clip is the best solution at this point, I have never used it before, but I imagine there is a first time for everything.

Hello,
I have the same problem, i want to downgrade from F.28 to F.27 because last update disabled my ethernet controller i can't open on bios settings, i try H20EZE with decryted firmware and i changed BIOS version F.27 to F.29 my problem is CHECKSUM,CRC32 changed after the version change , I cannot downgrade from HP Emergency Recovery and UEFI Dignostic Tool does not accept signature file, How can we change bios version without checksum change and CRC32. Can you help me? @Lost_N_BIOS

F.28 Latest version : https://ftp.hp.com/pub/softpaq/sp96501-97000/sp96570.exe

F.27 previous one : https://ftp.hp.com/pub/softpaq/sp93001-93500/sp93361.exe

My model is : 15-af113nt (AMD Processor - APU)

---------------------
@Lost_N_BIOS

Lost_N_BIOS Hi Can you help me too? I have the same problem like @Zeca123. I have Hp Notebook 15-da0056TX currently at F.23 BIOS, I would like to go back to the original BIOS F.11 but update cannot allow me. hope you can kindly help me. thanks

Hi @Lost_N_BIOS,

can you please help me downgrading this laptop bios: https://support.hp.com/us-en/drivers/sel.../model/13556168

from F.60 Rev.A to F.03 Rev.A ?

All .exe containing .bin and .s12 files are in the link

Lot of thanks

Regards

Edit:

I only want to change the version of the .bin file of an old bios so it can be flashed cause will be "Newer" as you said in your post.

@voug
Lost_N_BIOS? I haven't seen him active for a long time.

Hi @Sweet Kitten

Thanks for the attachment,
What can I need to do with the zip?

Is not .s12 file a requirement?

Has the .bin of the zip the BIOS version changed?

Thanks,

Regards

Hi again @Sweet Kitten
I tried what you posted and, after the computer restarts to install it I get "Unable to open bios signature file"

do you know which one of the files I can get extracted to "C:\Users\user\AppData\Local\Temp" (when I run official .exe of the bios in hp page) is the s12 signature file or how can I get it?

Thanks

I think I can obtain this file if I click on "create recovery usb flash drive" I'm gonna try...

Just tried manually copy-paste .s12 from the usb recovery drive but don't work, I get the same bios signature error. What I need to do ? Where I need to put the .s12 file?

Zitat von voug im Beitrag #25

---

What can I need to do with the zip?

---

Zitat von voug im Beitrag #25

---

Is not .s12 file a requirement?

---

Zitat von voug im Beitrag #25

---

Has the .bin of the zip the BIOS version changed?

---

Zitat von voug im Beitrag #26

---

Also the bios .bin file has different size from the ones from HP page, it is correct? it is safe to flash it?

---

@Sweet Kitten

Just tried with InsydeFlash and Start but after restart I get:

"Unable to open bios signature file"

how can I fix it?

Where I need to put this signature file? do you have it?

i get something like this image from hp site: https://h30434.www3.hp.com/t5/image/serv...7F145ECEDE?v=v2

@Sweet Kitten are you sure this won't brick my laptop?

I read this:

"The signature file contains the SHA1 hash of the signed signature and the SHA1 hash of the decrypted image. Since we don't know HP's private RSA key, then we can't modify the signature file to correctly match the modded rom.

Also, the signature check happens at startup since the code for this check is directly in the rom. Flashing the modded rom through any method isn't going to remove this code, so the check will still happen. I've had people experiment with flashing via InsydeFlash.exe, fptw.exe, the recovery utility, etc, and they all brick."

from http://web.archive.org/web/2016091621431...k-recovery.html

(link previously posted by LOST_N_BIOS in previous page)

Zitat von voug im Beitrag #28

---

Just tried with InsydeFlash and Start but after restart I get

---

Zitat von voug im Beitrag #29

---

are you sure this won't brick my laptop?

---