Is /media/user/My_hard_drive an existing directory? If not, try to create it:
$ sudo mkdir /media/user/My_hard_drive
That said, /media is supposed to be for removable media. You may want the directory to be directly in /.
Is /media/user/My_hard_drive an existing directory? If not, try to create it:
$ sudo mkdir /media/user/My_hard_drive
That said, /media is supposed to be for removable media. You may want the directory to be directly in /.