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No existing instance of WinVNC could be contacted

btaz
20
20
Posts: 39
Joined: 2005-03-10 22:59

No existing instance of WinVNC could be contacted.

Post by btaz »

The host is running UVNC 1.01 on WinXP SP2 with the firewall disabled. The UVNC server is installed as a service. The service starts automatically but the helper icon never appears in the tray. If I try to start the helper from the menu I do not get any error but the helper does not start.

If I try to display the default settings or the user settings through the menu I get the error shown in the subject. If I start the UVNC server as an application via the menus I can display the default and user settings dialogs.

Regardless of whether I run the UVNC server as a service or as an application I cannot connect across the LAN using the IP address of the server. I am not using the encryption plugin and and I am using the default port (5900). Uninstalling and reinstalling changes nothing.

Any suggestions? Thanks.
redge
1000
1000
Posts: 6797
Joined: 2004-07-03 17:05
Location: Switzerland - Geneva

Post by redge »

spyware pick hangapp !!!


For fix this issue:
find a very good anti spyware
or,
if you don't find it like me,
save yourd importants personal documents then format hard disk and re-install windows and install ultravnc and it work fine as service very well !
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
btaz
20
20
Posts: 39
Joined: 2005-03-10 22:59

Post by btaz »

A spyware scan did not help.

It's a lot less expensive to buy a copy of PC Anywhere than it is to reinstall Windows.<g>

I did not expect to find any spyware on this computer because the only thing it is used for is to allow the owner of the company to connect using remote desktop and run one app. Therefore, it is hard to imagine how spyware could get on this computer.

Thanks for the suggestion.

[mod=494,1127276084]merged all same title subject to one[/mod]
Last edited by btaz on 2005-09-21 04:14, edited 1 time in total.
Chris H
20
20
Posts: 47
Joined: 2005-04-16 01:59

Post by Chris H »

I had the same problem when trying to use Remote Desktop and WinVNC at the same time.

I've read about other people having the same problem.
btaz
20
20
Posts: 39
Joined: 2005-03-10 22:59

Post by btaz »

I never tried to use Remote Desktop and UVNC at the same time. I have the same problem at this site on another computer running XP Home so there is no remote desktop as an alterative on that one.
David II

Windows 2003 server standar. Error: No existing instance ..

Post by David II »

Windows 2003 server SBS.
No existing instance of WinVNC could be contacted
The service is runing....
the same as netwolf , running as program within existing session works good, running as service is unusable.

I tried everything from the forum. Is there some chance for quick solution, or you can suggest me another tool ? (need multiple users, security - crypt communication, little bit more speed, than realVNC)

Thanks, David
dngrtenr

I found the answer!

Post by dngrtenr »

So I'm upgrading my UltraVNC from some way older version, and I install it, and it doesn't work. The service is running, but every time I try to configure it (or run the service helper) I get the lovely error "no existing instance of WinVNC could be contacted".

So I reinstall. Nothing. I kill the service. Nothing. Delete the reg keys and reinstall. Nothing. Frustrated, I find this forum, find this topic, and... find I've already tried all the suggestions. Figure out that nobody really has solved it yet.

Well at least in my case, the solution was simple. I was trying to install / administer UltraVNC remotely, using remote desktop / terminal services. Here's the deal. When UltraVNC starts up as a service, and finds there is no password set, it won't really run... it just shows that window about needing to set a password before it will work. Well, it shows it only on the main display, not on a display obtained by terminal services.

Solution? In my case, walk my sorry self down to the basement and physically get on the machine. Start the service, and behold the popup window. Fill in the details, and voila! service is functioning normally.

Hope this helps !!
Guest

Post by Guest »

kwown as bug
[topic=3490][/topic]
curtis_rapp
Posts: 4
Joined: 2006-02-09 14:04
Contact:

No existing instance of WinVNC could be contacted

Post by curtis_rapp »

I encounter this problem when I am attempting to connect to the viewer's default settings when I am running the viewer on one of my domain's servers (2000 and 2003). When I am logged in as the local adminstrator account on my domain servers, I am able to pull up the show default settings and make my changes (encryption and MS Logon). What's got me hung up is the fact that my domain account is a member of a group that is an admin on all of our domain servers. I don't know if my problem is something specific to my domain, but for what its worth, if you're able to log in as the local admin, give it a try. It worked for me.
ultrarich
Posts: 2
Joined: 2006-03-11 00:33

Workaround Found

Post by ultrarich »

Hi,

I was having this same problem. I have NOT found a complete solution, however I have found a workaround that allows you to get the service up and running.

Follow these instructions exactly:
1. (I assume UltraVNC is already installed)
2. Stop UltraVNC Service
(make sure no instance is running via task manager)

3. Run UltraVNC in USER mode (i.e. by doubleclicking winvnc.exe)
You should see the tray icon.

4. If you right click on the icon and click "Admin Properties" you can enter your password and options etc and check the box "Accept connections" etc. as you prefer. However this is all ONLY for the CURRENT USER.

5. Now click the link to "Show Default Settings"
6. Enter your password, ports, etc. as you prefer. , this is REQUIRED and is for the LOCAL SERVICE

7. Close the user-mode WinVNC (nicely--using the tray icon).
8. Start WinVNC Service

You still cannot see the tray icon or set default settings etc. while it is running, but you SHOULD be able to connect to it remotely and do what you need.

Let me know if this helps anyone.
ultrarich
Posts: 2
Joined: 2006-03-11 00:33

Windows XP Fast user switching

Post by ultrarich »

I don't know how much this has been discussed, but Windows XP Fast user switching uses Terminal services also. I have noticed that you CAN access the Default settings of the service directly ONLY when you are logged on in the ACTIVE session.
Ie. open Task Manager>Users and look at the ID of the session you are logged onto. You can only access the service properties (and see the icon and set default properties for the service) when you are logged on with an ID of 0 (which is where all services run).
When you want to administrate the VNC server, log off all accounts. Then log onto an account with administrator priviledges. Now you should see the VNC icon and be able to change settings etc.

Hope this helps.
Also, see the last section of this post:
http://faq.gotomyvnc.com/fom-serve/cache/76.html
and this related one:
http://forums.windowsitpro.com/web/foru ... erthread=y
AmphetaMarinE
Posts: 1
Joined: 2006-03-14 02:12

Re: Workaround Found

Post by AmphetaMarinE »

ultrarich wrote:Hi,

I was having this same problem. I have NOT found a complete solution, however I have found a workaround that allows you to get the service up and running.

Follow these instructions exactly:
1. (I assume UltraVNC is already installed)
2. Stop UltraVNC Service
(make sure no instance is running via task manager)

3. Run UltraVNC in USER mode (i.e. by doubleclicking winvnc.exe)
You should see the tray icon.

4. If you right click on the icon and click "Admin Properties" you can enter your password and options etc and check the box "Accept connections" etc. as you prefer. However this is all ONLY for the CURRENT USER.

5. Now click the link to "Show Default Settings"
6. Enter your password, ports, etc. as you prefer. , this is REQUIRED and is for the LOCAL SERVICE

7. Close the user-mode WinVNC (nicely--using the tray icon).
8. Start WinVNC Service

You still cannot see the tray icon or set default settings etc. while it is running, but you SHOULD be able to connect to it remotely and do what you need.

Let me know if this helps anyone.
That is EXACTLY the problem I was having while trying to setup remotely using Term....
And you are a legend ultrarich.. your method worked PERFECTLY :)
Thanks a bunch mate :D
btaz
20
20
Posts: 39
Joined: 2005-03-10 22:59

No existing instance of WinVNC could be contacted

Post by btaz »

On one XP Pro SP2 machine I get the "No existing instance of WinVNC could be contacted" error dialog when I click View Default Settings from the menu. The WinVNC service is definitely running. On this same machine the service helper will not start either automatically or manually via the menu. When I try to start it from the menu I get the hourglass cursor for a few seconds then the cursor returns to normal. No error message and the service helper does not start.

Any suggestions? I am stumped.

[mod=494,1212780271]merged to existing topic you had already post and there the solution just above post #42[/mod]
Last edited by btaz on 2008-06-06 19:25, edited 3 times in total.
tylutki
Posts: 3
Joined: 2008-07-11 17:23

Re: No existing instance of WinVNC could be contacted

Post by tylutki »

I actually ran into the same problem, but did find a cure. Apparently the problem is running "Show Default Settings", which is winvnc.exe -defaultsettings. When I went manually to the program files directory of UltraVNC, and manually ran winvnc.exe by itself, it brought up the configuration window. I set my password, and then everything worked fine. ("Show Default Settings" worked after this as well.) Hope that helps.
PITmaster
Posts: 1
Joined: 2008-11-30 12:11

Re: No existing instance of WinVNC could be contacted

Post by PITmaster »

I had the same problem

The solution is to do everything according to information that appears after installing the service of server.
There is an ask to open service manager, find VNC Server and launch it.
So it's important to make it all imediately.
After lauching the service manualy, default settings will appear automaticly. Set the password and apply. Restart machine.

PITmaster
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