Can't write on harddrive

[Wollie]

Welcome here, @Nutzelfant

You are focussed on ownership and permissions but the key is first to mount the disk, correctly. I would do this:

[closed] NTFS, fstab, and mounting with read, write, and executable permissions

Unless USERNAME is your real username you have to replace that in fstab… Also the directory /home/$USER/d_drive needs to be created with mkdir. Furthermore, install ntfs-3g Then replace ntfs with ntfs-3g in your fstab entry and use the right options: UUID=43FBFFD71AD3FC68 /home/{username}/d_drive ntfs-3g uid=userid,gid=groupid,dmask=022,fmask=133 0 0

But here you also find a good guide how to generally mount a second disk:

[root tip] [How To] Use systemd to mount ANY device

Difficulty: ★☆☆☆☆ Disk device recognition Manjaro uses udev (see Arch Wiki) to load devices at boot time. The loading of devices is arbitrary and therefore you cannot predict which device will be available at a given path. But static device names do exist and you can assign specific locations to your device and thus ensure e.g. scripts will work as expected. What to learn Overview of system mount units Structure and Content of a mount unit Mount at boot (immediate mount) Mount on demand (m…