topic Re: EOS R5 Mark II 1.0.3 Firmware update in EOS DSLR & Mirrorless Cameras

EOS R5 Mark II How to update to firmware 1.0.3

BMikeW — Fri, 22 May 2026 14:43:04 GMT

I am a total idiot when it comes to all things computer. It took me over an hour to figure out how to access this forum, which I find almost impossible to use. (Pardon my frustration level.) I suspect that this kind of thing is a daily occurrence for most octogenarians. It certainly is in my case, at 83.

I received an email from Canon advising that firmware option 1.0.3 was available for my R5 II. I downloaded the update onto my computer and am now stuck. I recall updating firmware on my 5D II or 5D III, I can't remember which, by putting the update on a memory card, inserting the card into the camera body, and uploading it there. The instructions for this update are either nonexistent, too well hidden for me to find, or so far beyond my skill level that I can't understand them. Note that when I bought this body I decided not to add it to my WiFi network because I would only run into the same issues I am now facing with the firmware update.

Is there a step-by-step set of instructions available for idiots hidden somewhere that I could access? Canon, like so many companies these days, takes your money, but never wants to be bothered talking to customers again.

Thanks for reading my post.

Re: EOS R5 Mark II 1.0.3 Firmware update

Waddizzle — Fri, 22 May 2026 10:42:17 GMT

The exact details vary slightly depending upon your operating system. The main difference is the file extension of the file that you download.

First and foremost, you want to have only one memory card in the camera during the update.

Windows users download a ZIP file, which contains a FIR file. Open the ZIP file using File Explorer. Copy the FIR file to an empty memory card. No other files should be on the card.

Insert the card in the camera and turn it on. The touchscreen is disabled during an update.

Re: EOS R5 Mark II 1.0.3 Firmware update

shadowsports — Fri, 22 May 2026 11:21:54 GMT

Greetings @BMikeW

I think the only other thing worth mentioning is that instructions for the update procedure are included in the same file that you downloaded. The file that you downloaded is compressed. It contains the firmware update as well as instructions in PDF format. The file has to be unzipped or extracted to see its contents. This will also allow you to copy the firmware which has a .FIR file extension to the root of your SD card for the upgrade. One step that is often missed during the upgrade process is that you use the quick control dial on the back of the camera to move the menu option focus from Cancel > Ok, then press the Set button to execute the update. Hope this helps.