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"Server closed connection"- when running SingleClick

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spikepl
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"Server closed connection"- when running SingleCli

Post by spikepl »

I have the latest UVNC and just recompiled SC. I run the viewer in listening mode, and then run SC on another machine. Both run XP SP3. No fancy stuff, no encryption, just the minimum to make a connection. I have ZoneAlarm on both machines, bnut the result is the same whether switched on or off.

Whether on the LAN or WAN, the Viewer comes up with "Server closed connection", and that's that.

I did manage to run the SC before, two months ago, but having now tried so many combinations I simply no longer recall which versions ran correctly.

Googling did not reveal anyone else complaining about SIngleClick in the newest version, so what the heck can be wrong?
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Rudi De Vos
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Re: "Server closed connection"- when running Singl

Post by Rudi De Vos »

For testing i always create a test folder and put the files in it.
winvnc.exe
helpdesk.txt
...

This allow to make changes to helpdesk.txt without the need to recompile
each test.

Before testing remote, i start vncviewer -listen on the same pc as the
server and use localhost in the helpdesk.txt. To avoid any possible network issue's.

This need to work before you can do any remote tests.

You can also download the latest zip
http://www.uvnc.eu/download/winvnc_sc_2011.zip

just change the ip in heklpdesk.txt as first test.

Verify the viewer defaults, if you start vncviewer -listen, it still use the
saved defaults, like repeater, plugin etc....
Start vncviewer and delete default if needed.

The plugin used in this zip must also be used by the viewer, i didn't do any
test with the other plugins, rc4.key must exist on both sites and be the same. Included key is just for testing, for real life you need to create your own ( plugin config)

Hopes this help
Last edited by Rudi De Vos on 2011-04-19 14:16, edited 1 time in total.
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

Thanks for your posting.

I tried the localhost address in the file, and now run the winvnc.exe directly from the same folder as the modified helpdesk.txt (on the same machine) but no joy - still Server closed connection.

I have no repeater set up, nor any activated plugin (checked when running the viewer normally).

I had deleted my previouys VNC installation in Add/Remove Programs, and had deleted the remaining UVNC folder.

I do not think I have made any configuration changes to my machine since last time when SC ran successfully. Since it DID run, then I know it's possible, so you can imagine my frustration when I cant get the basic thing to run :-(

Any other suggestions? Is it possible it will not run without the plugins?
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

ANd with the supplied plugin, I again just get the Server closed connection, the Server running as application. :(
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Rudi De Vos
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Re: "Server closed connection"- when running Singl

Post by Rudi De Vos »

Try to delete vncviewer options
open vncviewer.exe
press delete button
close vncviewer

This does not get erased when you uninstall vnc, it only uninstall files that are created during setup, not the files what are added while running.

What's the viewer version ?
Does it work on your other PC ?
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

Viewer is 1.0.9.6

I ran the viewer.exe and pressed the delete button.

Unfortunately, still same result.

I can try the reverse route tomorrow, i.e. install the viewer on the other machine (that I don't have right now).

Will be back tomorrow.

Thansk for your help.
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Rudi De Vos
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Re: "Server closed connection"- when running Singl

Post by Rudi De Vos »

-A lot of people are using SC.
-Syntax is correct, sample helpdesk.txt with localhost works
( retested on my PC win7 X64)

It still look like some security software is blocking winvnc, breaks socket connect and cause this error on the viewer site.
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

Installed the Viewer on the secondary (to be supported) machine. Ran SC on it locally, works just fine.

Ran SC on my primary machine, connected to the viewer on the secondary just fine. (That machine runs ZoneAlarm and Avast, like my primary)

So there must be something on my primary machine that screws up the UVNC...

I uninstalled UVNC, ran CCcleaner, reinstalled latest UVNC Viewer.

I tried to run the viewer on port 5505, and the SC, locally, on same port. Whammo: Server closed connection .... the Server is running as application.

So there seems to be an issue with my own machine. I disabled both ZoneAlarm and Avast, still the same result.

Where to look?
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

Anybody with a suggestion or hint as to how to diagnose the problem? For I'd prefer not to resort to reinstallation of the entire system.
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Rudi De Vos
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Re: "Server closed connection"- when running Singl

Post by Rudi De Vos »

Did you also tried it with firewall disabled or port 5505 added as exception.
if you download the full version, just winvnc.exe ( one exe) and run this
on the "bad" pc.
First run it ask a full and view only password.

method I
1) Now you can try to connect the viewer "normal mode"
you enter the ip address in the viewer
viewer connect to server

method II
2) viewer -listen
server: Systray "add new connection" you enter ip and port viewer
server connect to viewer ( same as SC)

The full version has more logging and can be saved (server props)
to file.

download server
[topic=27951][/topic]

Vista >=
Don't extract the zip via your browser !!!!!
Save zip and extract manual
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

I did try with disabled zonealarm, and antivirus. No effect.

To run the normal server and viewer on same machine did not work, because "Loopbacks not allowed", which does make sense.

On the Lan, I can run the normal server on my bad machine, and connect the viewer from my secondary machine, no problem.

The inverse is also OK - run full server on secondary machine, and connect viewer from my bad machine.

I then tried to run the viewer on the bad machine and the SC on the secondary machine, this time using port 5900, and then 39975. Still same problem as before.

Method I worked fine.

Method II did not (Server not found) - unless I give 5900 as port number.
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Rudi De Vos
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Re: "Server closed connection"- when running Singl

Post by Rudi De Vos »

The firewall is a MS buildin application, this has nothing to do with zonealarm or antivirus.
The ultravnc installer only open port 5900 in the firewall.

control->system and security-> windows firewall
Are the port you are using added as exception ?

Temp disable this firewall for testing, you never know.

inverts i mean:

1)start viewer on OK pc, the same way as for SC
vncviewer.exe -listen
2)Click on the systray winvnc (full) "bad" pc
There you have the option add new connection
Add ip viewer and connect.

This way, the connection is initiated by the server, using port 5500 (default).
The server connect to the viewer on port 5500.

If you connect via the viewer:
Viewer connect to server on port 5900 (default)

In and outgoing connections make a difference and have seperate firewall rules.
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

When I follow your recipe, I get: Connection failed - Invalid protocol

I can still connect normally, i.e. start up UVNC server on either machine,and start the viewer on the other,and then connect.

As to the windows firewall, it is always disabled, but just to be safe I also exempted port 5500 tcp on both machines
Last edited by spikepl on 2011-04-20 15:13, edited 1 time in total.
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

I tried the 5500 port from the outside, by running http://www.canyouseeme.org/ with port 5500, and the viewer in listening mode reacts

What else can I check?
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

I did some googling, and running
cmd and then
netstat -ano

should reveal if anything else was lurking in port 5500, but nothing turned up :(
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Re: "Server closed connection"- when running Singl

Post by Rudi De Vos »

out of answers...sorry.
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

Thank you for your help.

If anybody has any ideas, either for solving the problem or for diagnosing it, please do post them
YY
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Re: "Server closed connection"- when running Singl

Post by YY »

Hi! spikepl

Can you also check this:

1. at the "bad" pc, run the viewer at listening mode (i.e. vncviewer.exe -listen)
2. then the EYE icon will appear on Systray, hover the mouse pointer over it, what is the port being listen ? (in normal, it should be 5500)
3. When hover the mouse pointer on the EYE icon, right click & select "New Connection". The viewer GUI will pop up, what is the status of the "Use Dsmplugin" check box ?
spikepl
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Re: "Server closed connection"- when running Singl

Post by spikepl »

2. It is 5500
3. Unchecked
YY
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Re: "Server closed connection"- when running Singl

Post by YY »

So looks like it is working properly.
Out of idea too!

on 2011-4-20 spikepl wrote: To run the normal server and viewer on same machine did not work, because "Loopbacks not allowed", which does make sense.
You hadn't tried this test because the mentioned problem.
To make loop back connection possible, you need enable this option at Admin Properties.
Try this again with the Log function enabled, to see if this can find out the cause.

Good Luck
redge
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Re: "Server closed connection"- when running Singl

Post by redge »

spikepl
check on bad computer if you used DrTCP or any clone doing this TCP/IP optimization
put back default value network MTU 1500 for Ethernet or over DSL PPPoA
MTU 1492 for DSL PPPoE
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
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