Andere USB-Sticks und die externe Festplatte lassen sich auch nicht öffnen. Ich hatte dies mal ausgestet, um sicherzustellen daß es nicht am USB-Stick liegt.
karin@Hilde:~$ mount && ls -aluh /media/karin/Transcend/*
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=16272940k,nr_inodes=4068235,mode=755,inode64)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,size=3262404k,mode=755,inode64)
/dev/nvme0n1p2 on / type ext4 (rw,relatime)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev,inode64)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k,inode64)
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
efivarfs on /sys/firmware/efi/efivars type efivarfs (rw,nosuid,nodev,noexec,relatime)
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=32,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=7265)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,nosuid,nodev,relatime,pagesize=2M)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
/var/lib/snapd/snaps/bare_5.snap on /snap/bare/5 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/core18_2846.snap on /snap/core18/2846 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/core22_1380.snap on /snap/core22/1380 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/core22_1663.snap on /snap/core22/1663 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/core24_609.snap on /snap/core24/609 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/element-desktop_107.snap on /snap/element-desktop/107 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/firmware-updater_127.snap on /snap/firmware-updater/127 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/firmware-updater_147.snap on /snap/firmware-updater/147 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/gnome-3-28-1804_198.snap on /snap/gnome-3-28-1804/198 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/gnome-42-2204_176.snap on /snap/gnome-42-2204/176 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/gnome-46-2404_48.snap on /snap/gnome-46-2404/48 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/gtk-common-themes_1535.snap on /snap/gtk-common-themes/1535 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/kf5-5-113-qt-5-15-11-core22_1.snap on /snap/kf5-5-113-qt-5-15-11-core22/1 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/krita_104.snap on /snap/krita/104 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/mesa-2404_143.snap on /snap/mesa-2404/143 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/snapd_21465.snap on /snap/snapd/21465 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/skype_370.snap on /snap/skype/370 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/thunderbird_470.snap on /snap/thunderbird/470 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
/var/lib/snapd/snaps/thunderbird_532.snap on /snap/thunderbird/532 type squashfs (ro,nodev,relatime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)
tmpfs on /tmp type tmpfs (rw,noatime,inode64)
/dev/nvme0n1p4 on /home type ext4 (rw,relatime)
/dev/nvme0n1p1 on /boot/efi type vfat (rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,nosuid,nodev,noexec,relatime)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=3262400k,nr_inodes=815600,mode=700,uid=1000,gid=1000,inode64)
portal on /run/user/1000/doc type fuse.portal (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)
tmpfs on /run/snapd/ns type tmpfs (rw,nosuid,nodev,noexec,relatime,size=3262404k,mode=755,inode64)
nsfs on /run/snapd/ns/skype.mnt type nsfs (rw)
nsfs on /run/snapd/ns/firmware-updater.mnt type nsfs (rw)
ls: Zugriff auf '/media/karin/Transcend/*' nicht möglich: Datei oder Verzeichnis nicht gefunden
karin@Hilde:~$
ime,errors=continue,threads=single,x-gdu.hide,x-gvfs-hide)