topic Re: EOS R5 Mark II Unable to updater firmware in EOS DSLR & Mirrorless Cameras

EOS R5 Mark II Unable to update firmware

alanhann — Tue, 02 Dec 2025 14:12:09 GMT

I am trying to update the R5 MarkII firmware to v 1.2.0.

The firmware eos52-v120-mac.dmg downloads to my hard drive on a MacBook M1 okay.

But when I try transfer the unpacked file to the 512GB card by taking the small arrow on the screen and clicking on the small circle to the right it does not unpack to a fir file.

Any suggestions?

Re: EOS R5 Mark II Unable to updater firmware

shadowsports — Sun, 30 Nov 2025 00:45:40 GMT

Greetings,

The .FIR file is one of the files in the .dmg which needs to be extracted or unpacked. If you don't see if on your desktop when running from the same location, open preferences for your desktop and enable the show disks check box.

Once unpacked, copy only the .FIR file to the root of your memory card. Only have one card in the camera when you perform the update. Use the quick control dial to move the cursor to ok, and press the set button to execute.

Re: EOS R5 Mark II Unable to updater firmware

ebiggs1 — Sun, 30 Nov 2025 17:14:23 GMT

"Only have one card in the camera when you perform the update."

And I would have only the FW file on the SD. Nothing else. A FW update needs to be done exactly the way Canon instructs you to. They provide ample instructions on how to achieve it.

Re: EOS R5 Mark II Unable to updater firmware

Stephen — Sun, 30 Nov 2025 17:26:45 GMT

This might help - it's from a different firmware update earlier this year, but it shows you how to copy the file: