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Unable to connect two machines on a LAN

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Benjamen
Posts: 1
Joined: 2012-02-24 19:27

Unable to connect two machines on a LAN

Post by Benjamen »

I've recently installed the full UltraVNC 1.0.9.6.2 server/client app on a Windows XP pc and Windows 7 pc. The two machines are behind a NAT router (I've allowed connection through recommended port, although both machines are on a LAN). Both machines perform the loopback connection without fail. I've enabled File and Sharing for both machines. I've disabled firewall/anti-malware apps. When I try to connect the Win7 to WinXP or vice versa I get a "Failed to connect to server!" error, how or what could cause this issue? Thanks
B
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Joined: 2009-09-09 14:05

Re: Unable to connect two machines on a LAN

Post by B »

I would start by doing something like netstat/an from a command prompt on both machines to confirm that the VNC server is listening on the desired port (5900 by default).

Then from one machine, telnet to the other on that port and see if you get a response.

Of course be sure you are using the correct local IP address for the other machine.

Also try to get connectivity WITHOUT any encryption at first -- just use plain VNC password authentication...
e-ghost
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Joined: 2011-04-08 02:50

Re: Unable to connect two machines on a LAN

Post by e-ghost »

I have the same issue also since 1.0.9.6.2. :cry:

My VNC server is a Win7 x64, UVNC 1.0.9.6.2. I have my server running 24x7 in order to back me up when working on-site. The UVNC server should usually functional in the first few connection within few couple of days but sooner or later, I will encounter "Fail to connect to server" error. When I back home, I cannot kill the "winvnc.exe" at all (not allowed). I must reboot the server in order to get uvnc server work again for a period. But when will uvnc server fail is totally unpredictable so it caused me lost my home-server support during on-site work many times already. It almost killed me... :cry:

I have a vmware linux guest OS running on that server as well. When uvnc server fail, I tried to ssh in that linux and telnet the host's 5900. The port 5900 simply no response. So it is not WAN or NAT issue. Even on the same machine also cannot get response from host:5900 as well.
e-ghost
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Joined: 2011-04-08 02:50

Re: Unable to connect two machines on a LAN

Post by e-ghost »

This is my setting I always use. I enable "Capture Alpha-Blending" since I started use Win7. Anything that may cause this issue?

Image
with "mv video hook driver2" installed on my win7 x64. Not sure if these are related to my problem or not.

Thanks!
e-ghost
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Posts: 11
Joined: 2011-04-08 02:50

Re: Unable to connect two machines on a LAN

Post by e-ghost »

even no one can help me on the official forum? :|
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Rudi De Vos
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Re: Unable to connect two machines on a LAN

Post by Rudi De Vos »

Connect: The only options that can have an influence are the
display/port settings.
All other take effect after the inital connection is made.

When I back home, I cannot kill the "winvnc.exe" at all (not allowed).
Do you see 2x winvnc.exe, is there a tray icon ?
1x service << can not be killed, you need to use the service manager to restart the service.
1x app running in the user desktop.

It's hard to tell what cause it and what the solution can be.
Perhaps you can ativate the logging and try to log the lock winvnc.
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