Downgrade bios from 1.41 for T420s

[segacleop]

I have sadly learnt the it hard way, that Lenovo decided to block official downgrading from bios ver 1.41 for the T420s. Does anyone know of a reliable plan b procedure to downgrade the bios, all attempts to run official exe of older Bios files are met with errors pertaining to a different system etc. If anyone can help me out i'll be forever grateful.

[segacleop]

Figured it out, just flash the FL1 file using winflash and close your eyes and wait for a brick or a downgrade. I got a downgrade, my hatred for Lenovo is getting there slowly.

[dr_st]

I wonder how exactly they "block" the BIOS from being downgraded... By your evidence, it is not a 100% block.

[RealBlackStuff]

Lenovo is just trying to be as obnoxious as they can be (and it is quite successful with that!)
Look at all the BIOS-mods that are floating about!

[Trexie]

Sorry to ask this here, can i downgrade from 1.48 to 1.46 in a t420, can the method posted above work? Sorry for all the trouble

[jwjensen356]

Sorry to butt in about the T420S but I have a newly acquired T420. It has a 1.37 BIOS. is there a particularly optimum one for an upgrade?

[jaspen-meyer]

Lenovo is just trying to be as obnoxious as they can be (and it is quite successful with that!)
Look at all the BIOS-mods that are floating about!

Not everything which glitters is gold. Some of those bios mods are building botnets.

[Anonymo]

Figured it out, just flash the FL1 file using winflash and close your eyes and wait for a brick or a downgrade. I got a downgrade, my hatred for Lenovo is getting there slowly.

Can you let me know what fl1 file to flash?