TightVNC Connection Problem

You need to forward the following ports 5800 and 5900 tcpon your router and Firewall.

grtz

Davy

These machines are on a LAN.  So no router or firewall- just a switch.

What happens if you try to use the computer to connect to itself with VNC?  Don't type the password in, just see if it asks for one.

I'd be most suspicious of the firewall, though your comment about the problem persisting while the firewall was disabled says that should not be the issue.  Are you sure it is disabled for the type of network connection (Public, Private, etc.) that is being used?  I have resorted to permitting the specific port in Windows Firewall in order to get VNC to work.

Can you show the results of your Test-Netconnection?  I tried it on my computer (with VNC server properly working) and I get "False" for TcpTestSucceeded.

I use GPO to deploy Windows Firewall settings.  All machines that are being controlled by the "Windows Firewall GPO" have no problem with VNC connectivity.  Again, I did go into Windows services and completely disable the Windows firewall.  Problem with VNC connectivity persisted.

Here are the PowerShell results:

First is the problem machine.  Second is a machine that is working.

Windows PowerShell
Copyright (C) 2014 Microsoft Corporation. All rights reserved.

PS C:\windows\system32> Test-NetConnection co-ws42 -Port 5900
WARNING: TCP connect to co-ws42:5900 failed


ComputerName           : co-ws42
RemoteAddress          : 10.0.20.169
RemotePort             : 5900
InterfaceAlias         : Ethernet
SourceAddress          : 10.0.20.87
PingSucceeded          : True
PingReplyDetails (RTT) : 0 ms
TcpTestSucceeded       : False



PS C:\windows\system32> Test-NetConnection co-ws09 -Port 5900


ComputerName           : co-ws09
RemoteAddress          : 10.0.20.82
RemotePort             : 5900
InterfaceAlias         : Ethernet
SourceAddress          : 10.0.20.87
PingSucceeded          : True
PingReplyDetails (RTT) : 1 ms
TcpTestSucceeded       : True



PS C:\windows\system32>

I was in error about Test-NetConnection on my computer.  I have results similar to your "good" one.

Did you try having the machine connect to itself with VNC?  I'm presuming that it will also fail.

Any chance there is some other firewall present?

I cannot test connecting to the machine from the machine as a user is currently using the machine.

No other firewall present.

I am somewhat stumped on this one.

I'd try one other thing.  Disable RDP (and confirm that the computer can no longer be reached by RDP), change the VNC port to 3389, then try to connect to the computer with VNC on 3389.

Thanks.  Will do.

I am not sure why or how, but the problem resolved itself.  Prior to the resolution, all I did was disable the firewall, reboot, found the connection failed again, I then re-enabled the firewall, rebooted, and found the connection worked after this sequence of events.  So maybe something got 'hung' up in the firewall?  Anyway, thanks for the help.