chmod a freshly mounted external drive to set up writing access

Try this first,

umount /dev/sdb1chmod -R 0777 /mnt/external   

then mount with

mount /dev/sdb1 /mnt/external

or try

chmod -R 0777 /mnt/external

chmod -R 777 /mnt/external

No need to specify the device. You chmod the directory recursively.

However, usually external drives are formatted with FAT32 or some sort of Windows-compatible file system, which does not have POSIX / UNIX permissions. So this step may be redundant.

How is your drive formatted?

Have you tried writing to it as a non-root user?

A solution posted on behalf of the OP.

Update:

linux-wyee:/mnt # chown martin:users /mnt/external

See the results: - it is obvious that it works ;-)

martin@linux-wyee:/> cd mntmartin@linux-wyee:/mnt> ls -linsgesamt 4drwxr-xr-x 3 root root 4096 13. Dez 19:43 externalmartin@linux-wyee:/mnt> suPasswort:linux-wyee:/mnt # ^Clinux-wyee:/mnt #linux-wyee:/mnt # chown martin:users /mnt/externallinux-wyee:/mnt # cd mntbash: cd: mnt: Datei oder Verzeichnis nicht gefundenlinux-wyee:/mnt # ls -linsgesamt 4drwxr-xr-x 2 martin users 4096 13. Dez 22:01 externallinux-wyee:/mnt #

It works as you see now the user martin has got permissions.