Downgrade my BIOS because it has a bug????

[AliDarwish]

Hi. 

Yesterday I successfully upgraded my BIOS to F.63 Rev.A from a windows server installation on an mbr-partitioned HDD installed on my laptop. My main system is on the SSD and it's Linux. Due to my own stupidity I forgot what my previous BIOS version was.

But now the following: after the BIOS update when pressing F9 no mbr-partitioned hard disks or usb drives will be seen as bootable anymore so I can't boot into my windows server installation anymore. I tried manually making a recovery drive by formatting a usb drive with a fat-32 partition with label HP_TOOLS and copied the BIOS recovery folders in there but when starting while pressing windows key + b it won't be recognized.

when startin while pressing windows key + b and having the BIOS files in the /efi/hp folder on my local SSD it is recognized and recovery begins but ONLY when I have the same F.63 Rev.A bios file in the 'new' folder. Any older version will not be recognized and it will give an error that the files are not found or are corrupted.

I desperately want to downgrade my BIOS because it's riduculous that I can't boot from mbr-partitions anymore. 

For the record I have legacy support enabled.

What can I do?

[AliDarwish]

Update:

I have installed the HP Diagnostic tool on my hard drive EFI partition and now when i press f2 while starting up I get this menu where a rollback option is for BIOS

I have 2 files one named 085FA.bin and one named 085FA.sig from the previous BIOS release. When trying to roll back the BIOS it gives the error "Unable to open signature file".

I'm at a loss here now. How to fix this? Is it simply refusing to roll back?

Edit:

I double checked and the "Unable to open signature file" only happens when trying any other version than  F.63 Rev.A, reinforcing my suspicion that they blocked rolling back from that update. please help!

Update 2: I converted the disk to gpt and still not detected. I'm beginning to suspect that the new BIOS is not compatible with my hard disk while the older BIOS was. The main SSD works fine.

My hard disk is Hitachi HTS547550A9E384 (JE3OA50A)

I can acces and diagnose this hard disk when booted into the main OS on the SSD and it passes all tests. But BIOS simply won't detect it anymore.

[tk_srq]

@AliDarwish,

Many HP laptops simply do not allow bios to be downgraded. I'm afraid that yours is one of them. My old Pavilion has a rollback option but if I try it, it always shows the "sig file cannot be opened" error.

The reason you don't see Hard Drive in F9 after the bios update is probably because the legacy support is disabled, as bios settings are set to default after a bios update operation.  I suggest you enter F10 bios settings and change the legacy support back to "enabled."

[AliDarwish]

Hi thanks for answering.

Sadly, I triple checked and legacy support is defeninitely enabled. I'm at a total loss here.  

[AliDarwish]

Hi thanks for answering.

Sadly, I triple checked and legacy support is defeninitely enabled. I'm at a total loss here.