Cannot connect to WInXP box with UltraVNC
peter "at" coulter.ndo.co.uk
Mon Mar 8 20:49:01 2004
Follow-up to earlier posting.
Test: Switched off NIS SW firewall entirely on the home
Result: Exactly the same as before (when NIS SW firewall was on and
ports 5500, 5800, 5900 were open in both directions to WinXP box); same VNC
Authentication screen displayed, and if done via IE with the VNC server host
name of the WinXP displayed on the remote (i.e office) PC. Password entewred
and same error message ("network error: no route to server <server name>")
Conclusion: This doesn't prove conclusively that there are no issues
with the NIS SW configuration, but it does prove that something else other
than the NIS SW firewall is stopping the comms. I do not believe it is the
Netgear HW firewall because I can see traffic going both ways across it and
the traffic is arriving on the WinXP box (using Ethereal). I suspect it is
the corporate firewall which is almost certainly not configured to let 5800,
or 5900 traffic past I suppose and I have no control over that. Perhaps I
don't quite understand the underlying implemention of the JM (IE browser)
version. Does it redirect from port 80 (HTTP port) to use 5800/5900? Or why
doesn't UltraVNC function via the IE browser ?
Meanwhile I am hastily switching NIS SW firewall back on! :-)
Also could resorting to using PuTTY solve any issues?
> -----Original Message-----
> From: Scott C. Best [mailto:sbest "at" best.com]
> Sent: Saturday, March 06, 2004 7:55 PM
> To: vnc-list "at" realvnc.com
> Cc: peter "at" coulter.ndo.co.uk
> Subject: Re: Cannot connect to WInXP box with UltraVNC
> 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,
> > 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
> > resolve my Dynamic IP address. The Netgear is set to
> > port-forward 5900 & 5800 to WinXP and 5901 & 5801 to 98SE