http://gzo4vfaflwt57dyamf2fpgfbcbejgcsq3n5acdn3ypdi2jpsa6qm7lad.onion/pmv/app.php/help/faq
Otherwise, you must link to an image stored on a publicly accessible web server, e.g. http://www.example.com/my-picture.gif. You cannot link to pictures stored on your own PC (unless it is a publicly accessible server) nor images stored behind authentication mechanisms, e.g. hotmail or yahoo mailboxes, password protected sites, etc.