I have a samba server set up behind my router, and I want it to be accessible to people outside the network (over the net). What ports do I need to forward to my Linux box? Just forwarding 139 doesn't do the trick. I have been told that only VPN, or putting the box "outside" the router will work. Is this true? It seems hard to believe.

BTW, I know that FTP is a better and more secure way to do this, but the people that need access are a bit tech-illiterate and would not use an FTP type setup, no matter what kind of coaching I give them. The files shared will be accessed and altered/appended frequently, so up/downloading via FTP would be intimidating and cumbersome for them. So, unless there is a way to make FTP behave like a Windows share (I'm open to suggestions; personally, I'd rather use FTP), I'll have to stick with samba.