Before erasing and partitioning your Kobo always back up your SD card and make sure you have an image of your Kobo drive before beginning this process.
I no longer own a Kobo Glo and do not have any Kobo images. The best place to find help with Kobo images or a bricked device are the forums at https://www.mobileread.com/forums.
You will need:
- Kobo Glo HD (or other Kobo model that uses microSD)
- New, larger microSD card (like SanDisk 32GB 98 mb/s $15.99)
- microSD reader/writer (like IOgear's $5.99 reader)
- spudger to open the backing of the Kobo and pull out the microSD card
- a program to re-partition and resize partitions on your microSD card like Gparted, either on your computer or on a bootable USB
We'll create an image of the current Kobo drive. We will copy all 3 partitions of the Kobo drive, including the operating system not just the e-reader's library of books. Otherwise, we'll have a library of books but no OS to run our Kobo e-reader.
Use spudger to lift up and off the Kobo's backing. Start near the usb port at the bottom and edge around the case.
Remove the microSD card being careful not to touch the exposed circuit board.
Put microSD into card reader. You should see the drive mounted and displayed on your Desktop. It should be called KoboReader.
In the terminal run diskutil list . Find and make note of the name of the volume that is your microSD card.
Make a copy of the microSD as an .img file by running dd if=/dev/$volume_name of=kobo_sdcard.img bs=4m
This copies the SD card to a an .img file in the current directory named kobo_sdcard.img with a block size of 4 MiB.
Remove the old microSD and replace with new, larger microSD card in the read/writer.
Write .img to it with the command dd if=kobo_sdcard.img of=/dev/$volume_name bs=4m
If you run this command on Linux, you need to upcase the m in bs=4m to be bs=4M.
If you get 'resource busy' message on macOS, then unmount sub-partitions as suggested here: https://unix.stackexchange.com/questions/271471/running-dd-why-resource-is-busy
Use the diskutil umount $filepath_to_sub_partition command.
We cannot use the macOS Disk Utility program to resize the partitions on our microSD. I did not have luck getting a live USD with gparted on it to boot with my Mac. However, I had previously created a live USB with Kali Linux which comes with Gparted. Either way your Mac will need to have an EFI boot loader, because currently macOS will not find your USB drive to boot from.
Download REFind boot loader:
Unzip the REFind file and note the location of the folder.
Reboot your computer, holding down CMD + R to boot into 'recovery mode.'
Click on Utilities in the task bar at the top of the window, and choose Terminal.
Turn off SIP by running csrutil disable command in terminal.
Reboot computer into recovery mode with CMD + R.
Click on Utilities --> Terminal and cd into the REFind folder location. Run the install script with the command
./refind-install.
Re-enable SIP by running the command csrutil enable. Reboot computer as normal to finish re-enabling.
On successful reboot, you should see the REFind boot loader display with all available disk drives. Insert Linux USB drive if not already inserted and choose to boot from it.
Insert SDcard intro read/writer if not already inserted.
Open Gparted. Find your device in the dropdown menu in the upper right hand corner.
Right-click on all partitions of the device and choose unmount. Unmount all partitions for the SDcard otherwise this
won't work.
Right-click on the non-Linux partition and resize to grow. This will be added to a queue in Gparted.
Click on Apply changes in Gparted to start the resizing.
On successful finish, reinsert new card into Kobo and power on. To check that your have successfully resized the storage of your e-reader, on your Kobo check 'Settings' and then 'Storage'. You should see the increased size of your storage.
Thanks