Unable to upgrade Z4 G4 BIOS from P61 version 1.61 to 2.82

[makruger]

Hello,

I have a number of workstations where I am unable to upgrade the BIOS. Most are already P61 2.x and those I can upgrade to version 2.82 without issue. However, I also have several machines which are a little older and running a P61 version 1.61 BIOS. These I am unable to upgrade directly to version 2.82. Is there perhaps a step up BIOS required here?

Looking through the release notes for 2.82, I noticed the following:

WARNING: AMT must be enabled before downgrading from any 2.XX BIOS version to any 1.XX BIOS version. This requirement is due to a ME Firmware mechanism incompatibility between these different major BIOS versions. After a successful BIOS downgrade AMT can be disabled

On all of my systems, AMT is disabled, but the management engine is running. However, enabling AMT didn't solve the problem. 

At this point it's worth mentioning that I have been using the bootable ISO method and looking closer I now realize the error message states it cannot find the binary in the paths it's searching (apparently these older BIOS versions are searching the hard drive EFI partition instead of the ISO). So, I decided to try the Windows updater from within the OS and this seems to work. I was able to migrate to a 2.x version and then use the ISO to get to 2.82 where it now does find the binary OK. I prefer using the ISO since it does not seem to require disabling bitlocker, which is convenient. 

My issue is now solved.

Thanks!

[NonSequitur777 · Accepted solution]

@makruger,

Welcome to our HP User Forum!

Thank you for your outstanding research and finding the solution!

Suggestion: you can close out your own thread/message ("accept as solution") so that your solution can be found more easily from a search engine and help others.

Kind Regards,

NonSequitur777