Cannot connect to WInXP box with UltraVNC

Scott C. Best sbest "at" best.com
Sat Mar 6 19:56:01 2004


Peter:
	Heya. Akshally, I think GoToMyVNC is telling the truth:
if your VNC Viewer can connect to the VNC Authentication prompt,
then the connect attempt is reaching your VNC Server. It's just
that something bad happens after that. :)

	You say below that 'both software firewalls have set the
local sub-net to "trusted and let all through"'. And that works,
but you can't connect from somewhere off your LAN. So...aren't
the software firewalls just doing their job?

	I know you don't want to, but please try connecting to
the VNC Server with the softwaree firewalls fully disabled. If
you don't have any AuthHosts settings in your VNC Servers, then
I don't think it could be anything else but them.

good luck,
Scott

> I've crawled all over the documentation, and through a lot of the mailing
> list (although admittedly not all), and cannot find what might be the
> problem and thus no solution. Apologies in advance if the solution is posted
> somewhere and I have missed it. Any suggestions what I might be doing wrong
> would be helpful.
>
> Situation:
>
> WinXP and Win98SE boxes behind a Netgear router. UltraVNC (server and
> viewer) installed on both. I am using a Dynamic DNS service IP to resolve my
> Dynamic IP address.
> The Netgear is set to port-forward 5900 & 5800 to WinXP and 5901 & 5801 to
> 98SE
>
> The WinXP box has Norton Internet Security (NIS, inc. Personal Firewall)
> installed. This is set to let ports 5900 and 5800 through. I do not use
> WindowsXP built-in "Internet Connection Firewall" and it is switched off.
> On the 98SE box the Freedom Personal Firewall is on.
> Obviously both software firewalls have set the local sub-net to "trusted"
> and let all through.
>
> Inside the Netgear router (i.e. on my LAN) all is well. Ultra-VNC works fine
> both ways from both boxes.
>
> Outside the Netgear is another issue.
> >From my office PC (which also has UltraVNC (server and viewer)) installed
> when I try to use UltraVNC I have no success.
> Ping does not detect the WinXP box because the router is set to not respond
> to ping, but I can log onto my router remotely by both IP address and
> dyndns-service-name and from there see the devices on the LAN just fine so
> connectivity is fine.
>
> The NIS logs show that the UltraVNC access attempt is hitting the NIS
> firewall - so the router is port-forwarding to the WinXP box correctly.
> When I try to access the WinXP box from the office PC using VNCViewer it
> fails returning the messages "Failed to connect server!". This the same
> whether I use <dyndns-service-name:0> or <dyndns-service-name::5900> to try
> to access VNC on the WinXP box.
> When I try to access WinXP box from the office PC using IE I get the VNC
> Authentication screen displayed, and the header bar is displaying the host
> name of my WinXP box; so it would seem that the attempt is reaching VNC on
> the WinXP box. But the response is always the same "Network error: unable to
> connect to server: <dyndns-service-name>".
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