Did you reformat the card when your laptop told you to?
That's a no-no.
Whether Mac or Windows your computer may have added a code during formatting the car does not recognize.

 

I did not reformat the card. It was an update on top of the existing map data.

 

I have exactly the same problem with my 2015 CX-5 after installing the December 2024 update to the SD card. I contacted Mazda and this was their reply:
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If the SD card card is recognized by your PC and Toolbox, but not by the MZD Connect in your vehicle, please check the software version in your vehicle. Proceed as follows:

• SETTINGS> SYSTEM> ABOUT> VERSION INFORMATION

If you are using a version below the 74.00.XXX, please contact your dealer for a system update.
Perform a factory reset on your Mazda Connect system:

• SETTINGS> SYSTEM> FACTORY RESET

Please note that all data currently stored in the system will be deleted. These include:

• paired phones
• Connected Wi-Fi networks
• Phone book
• destinations
• Radio favourites
• Display settings

If, despite the above tips, the problem still persists, and you can access your SD card using your PC, please send us the following information so that our specialists can investigate the issue.

We require a full diagnostic of your SD card including the signature files, which can be compiled via Toolbox:

1. Start Toolbox and connect your SD card.
2. Log in with your account.
3. Go to Settings > SD diagnostics.
4. Run diagnostics and, after it is done, and you see the results, underneath, click on "Check signature files".

Save the results in a text file.

Please also send us the following data:

1. A copy of the log files of the Toolbox, found under C:\Users\USERNAME\AppData\Roaming\Mazda\log
2. A copy of the http_dump folder of Toolbox, found under C:\Users\USERNAME\AppData\Roaming\Mazda
3. A screenshot of any error message.
4. A copy of the license folder of your SD card, found in the root directory of your SD card when connected to a computer.

Please compress the files in one or several .zip files.

If your SD card is not recognised by your PC and Navigation system, please contact your Mazda dealer and request a new SD card.

If you have any other question, please contact us again and indicate us the VIN of your vehicle.
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My version is 70.00.XXX so needs the firmware update. Mazda charge £150 for this so I am trying to obtain the EU version of the file to do it myself (I am an experienced computer technician). The factory reset did not improve matters. If I'm able to obtain the upgrade, I'll report back, but to me, it seems like Mazda have issued a faulty SD card update

 

My version below 74.00.xx.xx. Thanks for the tip, will consider it. I have also opened a support ticket and waiting for a response from the Mazda Toolbox team.

 

Firstly, many, many thanks to Ash8 for sending the link to the file and instructions to upgrade to 74.00.324A. A couple of hours on Friday afternoon and the software is now upgraded. However, the SD card was still not recognised, so the original problem was not resolved.
This afternoon (Sunday in the UK) I inserted the SD card into the PC again, mainly to gather data to send to Mazda, and I was offered another update to the card. This was a larger file than the previous one, but I am pleased to say that it worked! So, I reiterate that the December 2024 update was a faulty file, which has now been corrected.

 

My CMU is still 59.00.XXX, but these steps surprisingly solved the problem for me:

Make sure that the Mazda Toolbox is closed

1. Delete the download cache of the Mazda Toolbox, which can be found on the following file path: c:\Users\USERNAME\AppData\Roaming\Mazda\download_cache (Where the USERNAME is the actual name of the user’s profile in the operating system.
   The "AppData" folder under the USERNAME folder by default is hidden on the computer, so it needs to be made visible.)
2. Insert the SD card into the computer and save all its content for backup purposes
3. Delete all the files from the "content" folder from the SD card, but do not delete the "content" folder itself (Please make sure, that you do not delete any other files from the SD card)
4. Open the Mazda Toolbox and after the successful device recognition log in with your credentials
5. Select the "Settings - Manage - Manage content" option
6. Select the "Europe" or the "Russia and adjacent countries" option and press the "SELECT REGION" button
7. Press again the "SELECT REGION" button
8. After the successful installation, safely remove the SD card from the computer, insert it into the device and start the navigation
9. Please let us know if the above method has solved your issue.

So its not a problem of the CMU, but rather a bug in the map update procedure. If I removed all files from content folder forcing a full download of all files, then the navigation started work when inserting the card in the car.