Hi, I am stuck in downgrading the bios for my Supermicro h11dsu motherboard. I just updated the bios from 1.0a to 2.0b
here is the link for 2.0b https://www.supermicro.com/about/policie...wareItemID=9794
However, when I tried to downgrade (reflash ) a older bios such as 1.0a or 1.3. I always get an error showing:
1e - Error: Secure Flash function is not supported on this file.
I follow these steps to update the BIOS previously and use the same steps to downgrade the BIOS (no success):
Shell> fs0:
fs0:\> cd UEFI
fs0:\UEFI> flash.nsh H11DSUX.XXX
Does anyone meet the same problem before or any suggestions to solve the problem?
I found some posts online said it might be the USB portal problems or the space in the folder name. I have tried all my USB portal, reformat the USB as well as double check the folder name but no luck.
Waiting for some advice here.
Thanks.

Show me what text is in your NSH, show me image or copy/paste text. Never mind, I checked your link above. Does that NSH match the ones from older BIOS too?
If yes, please wait, I will check and let you know (may not be a safe/easy way around this without flash programmer)

* Edit, you can try adding /X after each place in NSH you see / flags being used.... example >> afuefix64.efi %1 /P /B /N /R /RLC:F << Add /X after that /R

This is a BIOS flash security thing, some BIOS do not allow it, some BIOS flash tools you need to use certain flags etc.

/CAPSULE << May be added after /X as well, but I would not try this without flash programmer in hand and backup made, thus programmer in hand this would not be needed anyway, so null point here unless you want to try it without programmer in hand and risk brick

Older ES AFU DOS will flash in the old BIOS with use of /GAN flag, but this is not suggested either because it's meant for old BIOS and can mess up future BIOS flashing, but it will work.

Personally, I wouldn't do anything here without programmer in hand, and then I'd just fix it that way instead (dump BIOS, have someone fix for you, don't program in old BIOS as-is or you will loose your board specific info serial, UUID, LAN MAC ID etc)

echo -off

set Debug_Mode 0

if %1 == "" then
goto Err_Print
endif

if not exist %1 then
goto No_File
endif

if %2 == "-d" then
set Debug_Mode 1
endif

if exist afuefi.smc then
mv afuefi.smc afuefix64.efi
endif

echo **************************************************************************
echo *
echo * Program BIOS...
echo *
echo **************************************************************************

afuefix64.efi %1 /K /RLC:F

afuefix64.efi %1 /P /B /N /R /RLC:F

mv afuefix64.efi afuefi.smc

goto END

:No_File
echo **************************************************************************
echo *
echo * %1 doesn't exist and please double check.
echo *
echo **************************************************************************
goto END

:Err_Print
echo **************************************************************************
echo *
echo "* Usage:"
echo "* flash.nsh romfile"
echo *
echo **************************************************************************

:END

if exist afuefix64.efi then
mv afuefix64.efi afuefi.smc
endif

:END1

* This is the NSH I used. I will try to add /X first. Thanks

I add /X flags so the code becomes:
afuefix64.efi %1 /K /X /RLC:F

afuefix64.efi %1 /P /B /N /R /X /RLC:F

The error are still there. And this is the results I saw.
FS0:\UEFI\> flash.nsh H11DSU7.825
FS0:\UEFI\> echo -off
Moving FS0:\UEFI\auefi.smc -> FS0:\UEFI\afuefix64.efi
-[ok]
...
Reading flash ...... done
1e - Error: Secure Flash function is not supported on this file.
...
Reading flash ...... done
1e - Error: Secure Flash function is not supported on this file.
Moving FS0:\UEFI\afuefix64.efi -> FS0:\UEFI\auefi.smc
-[ok]
FS0:\UEFI\> _

contact supermicro technological support for help , if they won't , you need SPI programmer.