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Maximus XII Extreme - "This file is not a proper bios" - Does not read any previous b

theotorm
Level 9
Hi everyone, currently on my maximus xii extreme I had the bios v.* 1003. I wanted to go back to the previous version 0901. I correctly formatted the usb key and renamed the file to .cap.* When I enter EZ-Flash and ask to read the file I get this error: "This File is not a proper bios." I can't go back!* I tried to download other earlier versions too (0804-0707 ... etc ..) ... nothing always has the same message!* Instead I tried to put the latest bios beta 2004 version and install it without problems!* I can't go back!
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2 REPLIES 2

HugoNabais
Level 7
theotorm wrote:
Hi everyone, currently on my maximus xii extreme I had the bios v.* 1003. I wanted to go back to the previous version 0901. I correctly formatted the usb key and renamed the file to .cap.* When I enter EZ-Flash and ask to read the file I get this error: "This File is not a proper bios." I can't go back!* I tried to download other earlier versions too (0804-0707 ... etc ..) ... nothing always has the same message!* Instead I tried to put the latest bios beta 2004 version and install it without problems!* I can't go back!


I have exactly the same problem! The latest bios is worse, less stable and I can't go back to any old bios. This file is not a proper bios...

On the back of your motherboard there is an USB port with a rectangle around it that says BIOS. Plug the USB stick in that USB port. Then press the button that says BIOS until it lights up, then let go. When BIOS button stops blinking the BIOS Flashback is done. Remove the USB stick. Power on computer, computer might power on and off one or two times.

See Video:
https://www.youtube.com/watch?v=28okjfzHMMA

or this video:

https://www.youtube.com/watch?v=bsv2MiInry4

Page 2-19 in your User's Manual to see where to insert USB and which BIOS button to press.

Note: EZ Flash 3 in BIOS is only an update BIOS utility. You cannot down grade to a previous BIOS using EZ Flash 3.
Page 3-3 in your User’s Manual. Therefore, use BIOS Flashback page 2-19 in your User’s Manual.