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Maximus XII Extreme - "This file is not a proper bios" - Bios Rollback

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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20 REPLIES 20

PerpetualCycle
Level 13
Did you try bios flashback?

ROG Hero XIII | 10900k @5.2 GHz | g.skill 2x32GB 4200 CL18 | ROG Strix 2070S | EK Nucleus 360 Dark | 6TB SSD/nvme, 16TB external HDD | 2x 1440p | Vanatoo speakers with Klipsch sub | Fractal Meshify 2 case

geneo wrote:
Did you try bios flashback?

What is Flashback bios? I always used EZ Flash from bios ... you can explain why I'm not very experienced ... thanks friend.

Page 2-19 in the User's Manual

Silent_Scone
Super Moderator
Redownload the file from the support site and use USB Flashback after renaming the CAP to M12E.CAP
13900KS / 8000 CAS36 / ROG APEX Z790 / ROG TUF RTX 4090

Silent Scone@ROG wrote:
Redownload the file from the support site and use USB Flashback after renaming the CAP to M12E.CAP

Sorry EZ Flash not good? I have already downloaded the bios 20 times and renamed them in .cap but I can't install them ... and the message is always the same ... I also changed the usb stick ... only the latest beta has updated the bios! What else should I do ???

theotorm wrote:
Sorry EZ Flash not good? I have already downloaded the bios 20 times and renamed them in .cap but I can't install them ... and the message is always the same ... I also changed the usb stick ... only the latest beta has updated the bios! What else should I do ???


Renaming is only a function needed for USB Flashback, use this feature as suggested above if wanting to roll back.
13900KS / 8000 CAS36 / ROG APEX Z790 / ROG TUF RTX 4090

Silent Scone@ROG wrote:
Renaming is only a function needed for USB Flashback, use this feature as suggested above if wanting to roll back.


i have also tried this both ways, renaming or not, and still not able to proceed on the Z490-E

hawkhandler wrote:
i have also tried this both ways, renaming or not, and still not able to proceed on the Z490-E


USB Flashback will work if following the process correctly.

Make sure the pen drive is

1) Freshly formatted to FAT32

2) In the correct USB slot

3)The file is renamed to M12E.CAP
13900KS / 8000 CAS36 / ROG APEX Z790 / ROG TUF RTX 4090

Silent Scone@ROG wrote:
USB Flashback will work if following the process correctly.

Make sure the pen drive is

1) Freshly formatted to FAT32

2) In the correct USB slot

3)The file is renamed to M12E.CAP


Unfortunately following the exact steps above and on the ASUS site still do not work for me.