5D MARK lll firmware update not working

[kariwright145]

I successfully installed firmware update on my R5 and was attempting to do the same with my 5D Mark lll. However, after trying 2 different formatted sd cards, downloading update to them and installing in camera, it keeps telling me memory card containing firmware is required to update. Can anyone tell me what I need to do? Not sure why same procedure worked just fine with R5 but won't with my 5D. I currently have firmware version 1.2.3 and the latest (or last) version is 1.3.6 Thank you!

[jrhoffman75]

Do you have two cards installed? Sometimes that causes a problem; if so try removing the one w/o firmware update.

[kariwright145]

No, only 1, the sd card that I formatted before downloading update. I tried the one I had been using forever already in my camera, then I tried the sd card that I successfully updated firmware with my R5. Reformatting for 5D first. I've checked and double checked that download was successful and on my sd card.

[p4pictures]

What is the capacity of the card you are using for the firmware update? If it’s 128GB or larger that might be part of the problem. 

[shadowsports]

Greetings,

We have to ask and ensure the 1.3.6 .FIR (firmware file) was placed in the root directory of the SD card?  I assume you did since the R5 Mark II update was successful. 

@Brian's recommendation sounds very probable at this point.  I've never checked the 5DmkIII's media slot requirements. 

[kariwright145]

1 card was 64GB, the other 128GB. The recommended perimeters. I just used the brand new 128GB I bought just for this on my R5 camera updates. I reformatted in my 5D when trying to do the updates in it. Had my camera set to P mode. All the steps I just did successfully with my R5 after watching several YouTube tutorials.

[kariwright145]

I selected correct most current up to date Sequoia for Mac. The download is on my as card, just not sure why 5D is not recognizing it. As I previously mentioned, I tried 2 different SD cards. A 64GB, and a 128GB.

[kariwright145]

Thank you, I triple checked that as well. I did the same steps I had just successfully updated my R5 with. It was the root, not any  sub folders.

[jrhoffman75]

Is the card slot containing your card selected as the playback slot?

[kariwright145]

It was set to record to multiple. I hadn’t changed anything as it worked fine with taking photos with just my SD card. My R5 was preset to standard and I only have an SD card I’ve been using in it. Just ordered a CF as a backup. I will try setting it to standard as well unless you suggest something different. Thank you!