"Could not open folder /media/USER/StorageZ" on fresh install of KDE neon. This folder is supposed to be my secondary HDD.

I used to have Ubuntu 18.04 on my laptop. Today, I installed KDE neon. I have 2 disks:

SSD (250 GB), containing my root directory

HDD (2 TB), which I used for big files (Steam games or movies). I named it StorageZ

When I wanted to format, I thought I would go the easy way, move all my files to StorageZ, and chose the first option in the installation (guided installation or something) and choose the SSD as the disk to work on. I thought everything should be okay, since the installation shouldn't even come near the HDD, which was true. But when I open Dolphin, I can see "StorageZ" on the left panel under "Devices". When I open it, it gives me a "Could not open folder /media/USER/StorageZ" (USER is my username).

I am still somewhat of a noob in Linux. I tried unmounting then remounting it, same problem. If I checked the properties of it, the files seem to be still there (it shows around 300 GB used).

The disk is in /dev/sda2. When I tried to mount it from the terminal, it gives me:

mount: /mnt: unknown filesystem type 'LVM2_member'.

At first, I didn't know what LVM2 means, after around a couple of hours of searching, I found a tutorial on how to mount those. When I reached the last step, which is

sudo mount /dev/ubuntu-vg/root /mnt/StorageX -o ro,user

it gives me:

mount: /mnt/StorageX: /dev/mapper/ubuntu--vg-root already mounted on /media/n7le/StorageZ.

Then I tried

sudo mount /media/n7le/StorageZ /mnt/StorageX -o ro,user

I got

mount: /mnt/StorageX: /media/n7le/StorageZ is not a block device.

I did a bit of search on that, but it is a whole new territory for me, and I don't want to risk deleting my files.

Thank you very much.

What file system type is on StorageZ? I always use ext4 (except for a few NTFS partitions I have around). During installation, I don't bother with other partitions/drives that I want to eventually mount, in fact I purposely don't do anything with them - I always use Manual and only select the partition I want to install on (selected as /, and tell it to format it) and select the swap partition. (The only exception is for /home, which I do on one computer as I have that as a separate partition.)

After installation when I'm personalizing the setup, these other partitions can easily be mounted with dolphin. To make it more permanent, I create mount points for the partitions (I put them in the root directory as that is the easiest to get to, i.e. /storageZ). This is done with a "sudo mkdir /storageZ" command. I then add an entry for the partition in /etc/fstab that looks something like:

UUID=<long uuid number> /storageZ ext4 defaults 0 2

And so that there are no permission issues, I then change the owner/user to myself from root with a "sudo chown -R USER:USER /storageZ" command where USER is my user name. Then un-mount the drive from dolphin and mount with a "sudo mount -a" command (or reboot). There's a couple of places where you can get the long uuid numbers, but the easier is with a "ll /dev/disk/by-uuid" command.

If you wanted to keep the "/media/USER/storageZ" path, I supposed to could enter this into the /etc/fstab patch. Perhaps there are easier ways to do this, but the above is what I have been doing for a long time now (since Linux Mint 10, aka Ubuntu 10.10).