Why can't I connect to my VNC server from outside my network?

Question

I have a computer running TightVNC server. It is on my home network. The computer it is installed on has a locally static ip address 192.168.1.100. I am able to connect to this vnc server from my home network fine, but unable to connect from outside my network (using the IP address that I see at www.whatismyip.com).

I have forwarded port 5900 (and 5800) to ip address 192.168.1.100. But if I use canyouseeme.org I am unable to see that port.

I am running Windows 7.

Any suggestions?

Answer 1

I would double check that you have forwarded the port as that is all you should need to do.

If there is a problem, try changing the default port in case your ISP is blocking it.

Lastly, you may want to double check that you have forwarded the correct protocol, I can't remember if it is TCP or UDP that is needed, but if you have one - try the other (or both!)

Answer 2

192.168.1.100 is a private IP Address that you will never be able to access from outside your network. You need to use the IP address of your modem. Your router does address translation that sees your 192.168.1.100 internally and when you send email or anything else on the net your router translates that IP into a public IP address that the "Cloud" understands. I do not know exactly how to set up TightVNC, but I do know that you need to be using your public address and not a private IP address. Hope this gets you going in the right direction.

Answer 3

According to this, you need to forward a 5800 as well.

Answer 4

The IP you listed is assigned by the router. Instead of attempting to access this address, you need to get the IP address that you're router is assigned by the ISP.

My IP address is 66.xxx.xxx.90 so I would need to enter this information (rather than the 192 series IP) in order to access my computer using TightVNC.

Another solution to your problem would be to sign up for a domain name using DynDNS.com (or a similar site), download their software and make sure it updates. What this allows you to do is access your home network using something like MyDomain.Mine.nu (which is how mine is set up). It is much easier to remember a name you came up with than those silly useless numbers.

Answer 5

From the other answers above, the only thing you are missing is to redirect any incoming connection to your OUTSIDE IP address to this fixed internal one. I agree that both ports 5800 and 5900 should be forwarded. If unsure, some of the routers will let you pick an IP address and make it DMZ, in that all incoming connections will be redirected to this internal IP address. However, it is not recommended for a permanent setup, only temporarily so you can eliminate other possible problems.

Some routers have the capability to actually update a DynDNS entry automatically, provided you give the proper credentials. Otherwise, most Dynamic DNS providers will also provide you with little utilities that will perform the same thing.

To make things more interesting, I have a static entry under my own domain name, which is a CNAME to my DynDNS one. So I'm not restricted to the domains that the DynDNS service provides. I can use my own ones. Such capability depends on what your domain hosting service lets you do. GoDaddy gives me total control. I can even break the entire thing........

Answer 6

I just tried canyouseeme.org from here and it seems to work as expected: sees the ports I know are open, doesn't see ports I know are closed. So it seems like a good tool.

If it's saying your ports are still closed, your ports are still closed. This could be due to your ISP, or any device in your connection path. It could also be due to your VNC server not running, so make sure it's running before testing.

Here's some things to check:

• Does Win7 have an active firewall? Could it be allowing local traffic on those ports but blocking external traffic? (If uncertain, disable it long enough to test.)
• What router make/model are you using? Latest firmware? Any other users reporting problems with forwarding?
• What's upstream from your router? Cable/DSL modem? Does it need to be configured to allow incoming traffic?