I have followed the instructions in the snap documentation for moving my data folder to an external drive, including adapting the config.php file and activating removable-media. It all works on a usb drive I have, but not on my main second harddrive that I want to use.
On looking closer, it appears that the (small) SSD Nextcloud snap is installed on has Disklabel type dos (Master Boot Record) whereas the big external HDD I want to move the data to is GUID Partition Table. They are both mounted in /media.
Could this be the reason why I am getting errors (can’t find data folder) when trying to move the data to this particular disk?
I would be surprised if such low-level things were the cause of your issues, here. Have you checked the permission of the data directory on the new drive, including all parent directories?
Maybe one beginner’s perspective thing: as someone not used to github, it took me ages to figure out that to access details on the Nextcloud snap wiki page, you have to select ‘Pages’ on the right. That’s a github issue, and not at all intuitive. But because beginners like me might likely try snap Nextcloud instead of the full server install, it might be an idea to add a note about that in the welcome message Home · nextcloud-snap/nextcloud-snap Wiki · GitHub.