Trying to connect to a computer on a client's network. He has a Netgear WGR614v9 router. I talked him through opening port 23 to 192.168.1.200. I have done this many times on other routers and it should have been simple but could not connect. Had him enable ping response so I could ping his router to verify the connection and ping was good. Tried my port scanner and only port 21 is open. Had client verify the port forwarding data and it is correct. Does he need to restart the router to enable port forwarding?
Well that is in fact the problem. They are on a DSL connection and their ISP blocks all ports unless they pay for a static IP address. Evidently cable ISP's don't do that because I have several clients on dynamic IPs on different cable ISPs and never ran into this with any of them.