Just to make thinks clearer: Do you now have a directory authorized_keys with the file id_urpo in it or a file authorized_keys containing the contents of the original id_urpo ? The latter is what Linux wants, I do not know about OS X. The browse dialog is limited to "N900" ( which is its default behavior), which obviously is a bug. I'll file a bug report on that so it's not forgotten about. You can still write the filename directly. You should use /home/user/.ssh/id_urpo instead of ~/.ssh/id_urpo