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Connection closes immediatly after (succesfull) connect ...

flloyd
Posts: 6
Joined: 2006-06-29 09:54

Connection closes immediatly after (succesfull) connect ...

Post by flloyd »

Hello.

First: Englisch is unfortunally not my natural language so please forgive me some errors :-)

Im not really a beginner in use of VNC, i used different versions several times over the last few years and never had any problems. For some weeks i used UltraVNC and it worked perfect and without any problems for me, but now i have the strange prolem, that immediatly after a succesfull connect the screen from the remote Computer opens for half a second and then closes again without any error message.

The ports are set (or forwarded) correct on the router/firewall, the connection works with the hostname or the ip-address, my authentication password is accepted - but then the connection closes again.

I have no idea what could be wrong. Local loopback works fine and i tried to uninstall and install the server again (also i tried RealVNC 4.1.2 to be on the sure side, but same problem with that one), i tried different ports than 5900 but nothing helped.

Any idea what the problem could be?

TIA,
Lloyd
bevtech
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Location: Pennsylvania, United States

Re: Connection closes immediatly after (succesfull) connect

Post by bevtech »

Do you have a password protected screen savor on the pc you are trying to remote too??
Bevtech

Windows XP Home, Pro SP2, Windows 2003 SBS server SP2(EN), Windows Media Center Editon 2005,Windows Vista Home Prem.,Fedora Core 6,Win9X, PChelpware Rel 1.0,
UVNC V 1.0.8.2

User not developer..;)
k-man
Posts: 4
Joined: 2006-06-29 12:55

Re: Connection closes immediatly after (succesfull) connect

Post by k-man »

i have this same problem also -and yes, the pc does have a password-protected screensaver

that's not supposed to make a difference..... i should see that prompt for a p/w of the SS when i connect
Last edited by k-man on 2006-06-29 13:05, edited 1 time in total.
flloyd
Posts: 6
Joined: 2006-06-29 09:54

Re: Connection closes immediatly after (succesfull) connect

Post by flloyd »

bevtech wrote:Do you have a password protected screen savor on the pc you are trying to remote too??
No. Just the Blackscreen-Screensaver without password-protection.
k-man
Posts: 4
Joined: 2006-06-29 12:55

Re: Connection closes immediatly after (succesfull) connect

Post by k-man »

[topic=5580][/topic]
When I try to connect to the VNC session running, I get the login screen prompting for the password. After I enter the password and click OK nothing happens.... the VNC viewer seems to dissappear....


Solution 1:

Make sure that the remote machine does not have a screensaver on, with the 'protect with pasword at wake up'

well, this isn't going to change
there is a screensaver and it has a password, and that's going to stay as it is

so, how do i get around or through that?
bevtech
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Re: Connection closes immediatly after (succesfull) connect

Post by bevtech »

k-man it will not work with a password protected screen savor..:( Remove the password and try it.. You cant get around it...:( Unless you enable mslogon and lock the pc when not in use..:)





flloyd does it work in a LAN???
Last edited by bevtech on 2006-06-29 13:16, edited 1 time in total.
Bevtech

Windows XP Home, Pro SP2, Windows 2003 SBS server SP2(EN), Windows Media Center Editon 2005,Windows Vista Home Prem.,Fedora Core 6,Win9X, PChelpware Rel 1.0,
UVNC V 1.0.8.2

User not developer..;)
k-man
Posts: 4
Joined: 2006-06-29 12:55

Re: Connection closes immediatly after (succesfull) connect

Post by k-man »

bevtech wrote:k-man it will not work with a password protected screen savor..:( Remove the password and try it..

ahhhh, no can do

the ss with p/w is required, as this pc is in an area where more than 1 person has access to it

i have not seen this problem with other vnc apps (radmin for one, but it sucks up 100% of cpu - horrible), so i can't see why it's a problem here
bevtech
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Re: Connection closes immediatly after (succesfull) connect

Post by bevtech »

k-man not sure what to tell you.. Mslogon II is probably your only way around that UVNC will not activate on a password protected Screen savor
Bevtech

Windows XP Home, Pro SP2, Windows 2003 SBS server SP2(EN), Windows Media Center Editon 2005,Windows Vista Home Prem.,Fedora Core 6,Win9X, PChelpware Rel 1.0,
UVNC V 1.0.8.2

User not developer..;)
flloyd
Posts: 6
Joined: 2006-06-29 09:54

Re: Connection closes immediatly after (succesfull) connect

Post by flloyd »

bevtech wrote:flloyd does it work in a LAN???
I dont know, i will try that @home and then report here :)

.
bevtech
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Re: Connection closes immediatly after (succesfull) connect

Post by bevtech »

flloyd home is a WAN connection.. LAN is pcs in the office on the same network locally..:)
Bevtech

Windows XP Home, Pro SP2, Windows 2003 SBS server SP2(EN), Windows Media Center Editon 2005,Windows Vista Home Prem.,Fedora Core 6,Win9X, PChelpware Rel 1.0,
UVNC V 1.0.8.2

User not developer..;)
flloyd
Posts: 6
Joined: 2006-06-29 09:54

Re: Connection closes immediatly after (succesfull) connect

Post by flloyd »

bevtech wrote:flloyd home is a WAN connection.. LAN is pcs in the office on the same network locally..:)
Yeah i know :) What i wanted to say is, that i will try it at home tonight because my LAN is at home :) From here in the office ill connect via WAN to my Home-LAN/Home-PC and i already know that the WAN-Connection does not work :wink:
bevtech
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Re: Connection closes immediatly after (succesfull) connect

Post by bevtech »

ok just making sure..;)
Bevtech

Windows XP Home, Pro SP2, Windows 2003 SBS server SP2(EN), Windows Media Center Editon 2005,Windows Vista Home Prem.,Fedora Core 6,Win9X, PChelpware Rel 1.0,
UVNC V 1.0.8.2

User not developer..;)
flloyd
Posts: 6
Joined: 2006-06-29 09:54

Re: Connection closes immediatly after (succesfull) connect

Post by flloyd »

After a long day in the office and a short visit at my grandfathers birthday after work i finally arrived @home and checked VNC over LAN. Pointed the VNC-Viewer to 192.168.0.2:port and it worked fine and without any problem.

And then again i tried it from the "outside" with both the IP-Address und with the hostname (provided by DynDNS) and it doesnt work both ways. If DynDNS would be the Problem it schould work with the IP but it doesnt.

LAN works
WAN with IP not
WAN with Hostname not

Now i am confused a bit ...
flloyd
Posts: 6
Joined: 2006-06-29 09:54

Re: Connection closes immediatly after (succesfull) connect

Post by flloyd »

@k-man
Did you find a solution?
bevtech
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Re: Connection closes immediatly after (succesfull) connect

Post by bevtech »

if it works via lan then the problem has to be a routing issue?? What kinda of connection do you have on the remote server. Some speedstreams have a firewall built into the their modems. Make sure that you are not fighting a firewall in between..:)
Bevtech

Windows XP Home, Pro SP2, Windows 2003 SBS server SP2(EN), Windows Media Center Editon 2005,Windows Vista Home Prem.,Fedora Core 6,Win9X, PChelpware Rel 1.0,
UVNC V 1.0.8.2

User not developer..;)
Maplassie
Posts: 1
Joined: 2006-07-24 09:23

Re: Connection closes immediatly after (succesfull) connect

Post by Maplassie »

Morning, and greetings from South Africa.

I have been experiencing this issue for quite some time, on 2 specific machines. I have been using Ultravnc for about 2 years now, and naturally I love it. I have 22 Firewalls that I monitor daily, each with about 20 users average. THat's a lot of users! LOL.

Anyhoo. I have this issue on 2 of my machines. Both are win98 Se Machines.I read through everything said on this page, and on the link in one of the above posts. I have made sure that neither of the machines have Screensavers with passwords.I have uninstalled and reinstalled VNC various times, each time installing the same version those 2 machines have, on my machine aswell.Then I tried older versions on those machines and newer one on mine, and visa versa.

It's definitly not firewall or port issues, cause they are seperate clients, on seperate firewalls. On the one firewall, I have 12 other win98 Machines, and 10 WinXP machines, that work 100%. The other has only 3 Win98 machines, of wich two work 100% aswell. The rest are WinXP machines also without any hassles.I also checked network settings and such, but no errors with that. Browsing the network, all computers can access the 2 win98 machines, and they inturn can access all the xp machines. I have tried logging into another machine on the network, and connecting to those 2 machines via IP, and Computername and it still does not work. BUt those 2 machines, can VNC into all the other machines locally on their respective networks, and abroad.SO it's definitly not port settings, or firewall. I even removed all Anti-spyware and Anti-Virus Progs, aswell as any security related proggies. Still nothing.

It just keeps on doing the same thing. I enter the password, it goes in, and immeddiatly closes. When I phone up those 2 specific ppl, and ask them if they see anything strange on the pc, or anything happenning as I connect, the only thing they see is the VNC icon in the taskbar changing color, and sorta like a screen refresh, and It kicks me out.I got RDC (Windows remote desktop connection) running on both 98 clients, and When I Use that to connect to the machines, it goes through, but does have some speed and stability issues. The thing is, it does get through, wich makes it strange why I can't use VNC to connect.

I say again, Both machines are @ seperate clients, on seperate networks and firewalls.BOth firewalls have win98 machines that work 100%.Both machines are win98Se, have no Anti virus, and no software firewalls/security proggies. Both machines can access any other machine locally via VNC and abroad, but they can't be accessed from any other computer via VNC, not even on the local network using Ip or computer name.

If it were firewall issues, or settings, then surely the other machines would have had the same issues?
I would gladly load XP on both machines, but strangly enough both clients refuse to have 98 on those machines. SO I really need to get it working.

Any any help would be greatly appreciated.

Thanx
redge
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Re: Connection closes immediatly after (succesfull) connect

Post by redge »

maybe tcp/ip stack issue with size of packet too big
try dr tcp
http://www.dslreports.com/drtcp



LAN = MTU 1500
WAN = MTU 1500 if ADSL PPP over ATM (PPPoA)
WAN = MTU 1492 if ADSL PPP over Ethernet (PPPoE)
VPN = MTU 1492 or less depend of the VPN and encapsulation
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
jftuga
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Posts: 36
Joined: 2005-05-31 18:31
Location: Athens, GA

Re: Connection closes immediatly after (succesfull) connect

Post by jftuga »

I am having this problem too. It happens sporadically on a spam new server, Windows 2003 EE. UVNC 1.02, no other version has ever been installed. It can happen even before the screen saver has time to activate. Restarting the winvnc service does not fix the problem either.

This is definitely a bug. I never had this problem with 1.01 with Windows 2003 on similar hardware. My main motivation for upgrading to 1.02 was because of the security fix.

FWIW, I do not use MS Authentication, just a standard password.

Any ideas?

-John
redge
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Location: Switzerland - Geneva

Re: Connection closes immediatly after (succesfull) connect

Post by redge »

on similar hardware
this similar hardware have same spam name of network interface card and same build of driver ?
Link speed and duplex are same ?
realtek had a lot of update last fews weeks for their network card.
related bugs of unstable network driver ?
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
bobwool
Posts: 2
Joined: 2006-07-27 03:53

Re: Connection closes immediatly after (succesfull) connect

Post by bobwool »

This is happening to me, too. I connect remotely (password only) to my home PC (WinXP Home SP2) and see the Windows login screen with buttons for two users: my wife (limited user) and me (admin). If I login as my wife, I can connect normally. If, instead, I login as myself, it takes my password and starts logging in, then my Viewer closes. When I connect again I get the Windows login screen again, only this time it says "Logged in" under my user name. If I try to login again as myself, the Viewer again closes.

I haven't been able to browse to my home PC from behind my router with my loaner Win2K laptop. Once I get my laptop back from Best Buy servicing I will try UltraVNC on my home LAN and see what happens.
bobwool
Posts: 2
Joined: 2006-07-27 03:53

Re: Connection closes immediatly after (succesfull) connect

Post by bobwool »

Ok, I found the solution to my problem in the FAQ. My wife never logs out when she's done on my home PC, so I set up her screensaver to resume with the Welcome screen, which allows quicker login for me when I'm home. With the VNC Viewer, I was trying to log in to my account while her account was still logged in. Following the FAQ, I logged in to her account, logged her out, closed VNC Viewer, then reconnected with the Viewer and successfully logged in to my account. My account does not resume to the Welcome screen, so I should be in good shape now.
edo660
Posts: 1
Joined: 2006-07-27 16:08

Re: Connection closes immediatly after (succesfull) connect

Post by edo660 »

this is a rather annoying bug...though it is very strange that i didn't have this problem (using screensaver + password protect) before using 1.02? go figure...using win2k3 std.
Fruitcake
Posts: 2
Joined: 2006-07-28 16:03

Re: Connection closes immediatly after (succesfull) connect

Post by Fruitcake »

I have been trying to setup a connection between two computers, both running Win XP Pro SP2 and behind a router, and I am experiencing the same problem as flloyd.
The following happens:
1. (viewer) Prompt for password, password filled in.
2. (server) Server icon (in application mode) turns green, wall paper disappears.
3. (viewer) Status: no bytes are being transferred.
4. (server) After a couple of seconds, connection is terminated.
No error messages are displayed.

Neither side is using a password protected screensaver.
The strange thing is that the connection works in one direction, but not in the other. I've tried both versions 1.01 and 1.02.
In short:

PC 1 (viewer 1.02) ====> PC 2 (server 1.02) WORKS (application mode)
PC 1 (server 1.02) <==== PC 2 (viewer 1.02) FAILS (both service and application mode tested here)
PC 1 (server 1.01) <==== PC 2 (viewer 1.01) FAILS (application mode)

I have checked the debug log-file, and these lines seem to indicate the problem:

S:\UltraVNC\winvnc\winvnc\vsocket.cpp : zero bytes read2
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncservice.cpp : SelectHDESK to Default (28) from 28
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncservice.cpp : SelectHDESK failed to close old desktop 28 (Err=170)
--The requested resource is in use.
S:\UltraVNC\winvnc\winvnc\vncclient.cpp : client disconnected : 127.0.0.1 (1)
--The operation completed successfully.
(...)
S:\UltraVNC\winvnc\winvnc\vncservice.cpp : SelectHDESK to Default (28) from 28
--Access is denied.
S:\UltraVNC\winvnc\winvnc\vncservice.cpp : SelectHDESK failed to close old desktop 28 (Err=170)
--The requested resource is in use.
S:\UltraVNC\winvnc\winvnc\vncserver.cpp : desktop deleted
--Invalid window handle.

Because I am using the NAT2NAT Connector to setup a connection, the viewer connects to the localhost (127.0.0.1).
I can post the complete log file if that helps.

I have tried setting the MTU size to 1492 (applicable in my situation) using Dr. TCP on both sides, but the problem remains to exist.

I would be very grateful if someone is willing to look into this problem.
basil.cinnamon
Posts: 1
Joined: 2006-08-02 23:05

Re: Connection closes immediatly after (succesfull) connect

Post by basil.cinnamon »

Same problem ever since upgrading from RC17 or so.
[Simple MS Windows workgroup LAN; internal VNC from one PC to the other (i.e., no router, firewall, etc involved). No screen saver, no ZoneAlarm.]

winvnc.log has the following, which may be useful to the developers:
... after the password stage,
S:\UltraVNC\winvnc\winvnc\vncdesktop.cpp : initialising desktop handler
--This function is only valid in Win32 mode.
S:\UltraVNC\winvnc\winvnc\vncDesktopSW.cpp : SWinit
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncdesktopthread.cpp : Hook changed 1
--The specified procedure could not be found.
S:\UltraVNC\winvnc\winvnc\vncdesktopthread.cpp : Hook changed 2
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncdesktop.cpp : KillScreenSaver...
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncdesktop.cpp : InitVideo driver Called no Temp_Resolution
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncdesktop.cpp : Driver option dsiabled
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncdesktop.cpp : No driver used
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncdesktop.cpp : Failed m_rootdc
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncdesktop.cpp : InitBitmap Failed
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncserver.cpp : Desktop init failed, unlock in application mode ?
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncclient.cpp : client Kill() called --The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vsocket.cpp : closing socket
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncdesktop.cpp : killing screen server
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncserver.cpp : Authenticated() done
--The specified procedure could not be found.
S:\UltraVNC\winvnc\winvnc\vncserver.cpp : RemoveClient() done
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncclient.cpp : ~vncClient() executing...
--The operation completed successfully.
S:\UltraVNC\winvnc\winvnc\vncclient.cpp : deleting socket
--The operation completed successfully.
...

Whatever "vncdesktop" is, it seems to be at the heart of the problem.
radioengineer
Posts: 1
Joined: 2008-01-11 18:01

Re: Connection closes immediatly after (succesfull) connect

Post by radioengineer »

I am experiencing this issue as well. I have 3 home computers with UVNC 1.02 viewer installed on them. One running Vista, one XP pro SP2, and one Win2000 Pro SP4. I experience the issue on every computer.

When I try to connect to my office computer, I get the log in. Type in my password. I am not using any plugins or MS Login. The box in the upper left corner of the screen say password accepted. It appears the viewer screen is going to load, and then just disappears. :|

My office machine is Win XP Pro SP2, no screen saver password, no screen saver. The graphics card is on the motherboard and it is the Intel 82945G Express Chipset.

I have had my wife try from home when I am at my computer, and it seems to work fine.

When I leave work all I do is lock my computer using the windows key and the L key.

The other odd thing, is it was working for the last 3 weeks, and then last weekend I tried to log in and it no longer works. :yell:

I have uninstalled UVNC and did a search of my computer for any vnc files, deleted them, and searched the registry, and deleted those entries as well. I then re-installed after a re-boot. Still the same issue.

I will have UVNC log everything so I can post a log file if needed.

Any thoughts on this would be appreciated.
metzor
Posts: 1
Joined: 2008-01-23 01:33

Re: Connection closes immediatly after (succesfull) connect

Post by metzor »

I've been having a similar problem. I've been connecting from home to my office's VPN, then to my individual desktop @work through ultraVNC viewer. Both computers are XP Pro. I've been doing it this way for the past 3 or 4 months with no problems.

Then suddenly I tried logging on from home and it doesn't work. I can connect to the VPN, but attempting to connect through VNC viewer gives me a "Your connection has been rejected" twice, then on the third try it lets me enter the password, says password accepted, then it seems to just exit completely with no error message.

What would cause this? I leave my office pc on "locked" all the time with the vnc server running, and have not had a problem for months. There is no password on the screen saver.

Anyone know anything?
ravenous28
Posts: 6
Joined: 2007-05-29 13:05

Re: Connection closes immediatly after (succesfull) connect

Post by ravenous28 »

You can count me in with the same problem I installed the server on 2 pc and try to connect with the viewer 1...fails...then try again...2 fails.....then try for a 3rd time..it ask me for the password..i type it in...opens up for like 2 seconds and closes.... i hope someone has a fix for this.
ravenous28
Posts: 6
Joined: 2007-05-29 13:05

Re: Connection closes immediatly after (succesfull) connect

Post by ravenous28 »

Im wondering if there was some kind of microsoft update that just came out that is causing problems now...this is pretty strange...i did nothing out of the ordinary with the install of the vnc server on the 2 pc's.
sphor
Posts: 2
Joined: 2008-05-08 23:15

Re: Connection closes immediatly after (succesfull) connect

Post by sphor »

I'm having the same problem as well. I notice the post was last replied in Jan. So I'm not sure if anyone has found a solution for this problem yet.

Would really appreciate it if someone can help.
sphor
Posts: 2
Joined: 2008-05-08 23:15

Re: Connection closes immediatly after (succesfull) connect

Post by sphor »

Nevermine. It just seems like I have to choose other option (not "Auto"), then it connects fine.
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