EOS Rebel SL2, EOS R10 GPT formatting bug for SD card

[nicolesharp100]

Just an FYI, but both the Canon EOS Rebel SL2 and the Canon EOS R10 appear to have the same bug whereby if an SD card with a partition table formatted as GPT is reformatted by the camera, then the card can no longer be read or mounted by Microsoft Windows 11.  Steps to reproduce the issue and fix it are given below.

Format SD card as exFAT or NTFS with GPT on Microsoft Windows 11.

Insert card into camera and reformat.  Camera will reformat to exFAT with MBR, removing GPT.

Take a photo and remove card from camera.  Card can no longer be read or mounted by Windows 11.

Replace card back into camera.  Copy photo to computer using USB connection to camera.

Remove card from camera and insert into PC card reader.  Delete exFAT partition.

Use Paragon Partition Manager Community Edition (or GPartEd) to:

--- convert partition table from MBR to GPT

--- convert partition table from GPT back to MBR

Recreate exFAT partition on MBR.  Insert card into camera.  Card will now work on Windows as normal.

What I think is happening is that the Canon camera has a bug that creates a bad MBR partition table if the card was originally formatted as GPT.  The card can then be read by the camera but not by Windows.  The only way to fix this is to format back to GPT and then reformat back to MBR to recreate the Windows-compatible MBR partition table.

GPT is supposed to be more reliable than MBR so when I started reformatting SD cards as GPT it took me a while to figure out why I couldn't mount the SD cards any more after they were used in the Canon camera and then how to fix the problem.

[shadowsports]

Greetings,

Maybe this will help.  The partitioning scheme of your computers HDD, SSD or M.2 drive does not affect or limit the formatting you can apply to internal or external disks. This is determined by the OS.  Why you decided to format your memory card GPT was your issue.  This formatting scheme is not supported. It can be corrected using a command line or powershell.  Paragon or GParted are not needed.

A MBR partitioning scheme allows up to 4 logical partitions.  A GPT partitioning scheme allows for 128 partitions.  However, you would never use or need this partition support on a CF Express / B or SD card intended for a camera.  The camera's inability to properly detect and format a card with unsupported formatting is not a bug or defect.  This is as designed.  DryOS was never intended to support GPT.  

Hopefully this will help others avoid issues.