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Winvnc server crashes when DSM plugin is used

Should you have problems with the DSM plugin, here's the place to look for help or report issues
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amn0270
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Winvnc server crashes when DSM plugin is used

Post by amn0270 »

When I use the DSM plugin, the server aka winvnc.exe crashes. The viewer does not crash, but it seems to get hung up on negotiating protocol. The server however crashes and shuts down. When I attempt the same connection without the plugin enabled they connect fine. I'm using version RC202 with both server and viewer. The server is on an XP pro machine and the viewer is on a 2000 server machine. Any ideas?

Thanks in advance,
Adam
redge
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Post by redge »

host: RC20.5
viewer: RC20.6

Did you use WLAN and WEP/WPA encryption with your UVNC and dsmplugin ?

if yes, is a poor quality of your Access Point
I have same issue
but with dsm plugin and without encryption WEP/WPA of WLAN, there no crash
Last edited by redge on 2005-04-16 04:01, edited 2 times in total.
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
redge
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Post by redge »

workaround
for WLAN Access Point (AP) low cost
(out of topic but help this problem for many users ;-))

example with: zyxel prestige 660hw serie
open your favorite web browser.
http://192.168.1.1
enter your password of your router
Advanced Setup... Wireless LAN
802.1x/WPA
  • ReAuthentication Timer 1800 (factory) --> 9999 (user)
  • Idle Timeout 3600 (factory) --> 9999 (user)
    ...
  • WPA Group Key Update Timer 1800 (factory) --> 9999 (user)
Apply
Logout

I had never crash again the vncviewer+AESplugin and the AP WLAN with enrypted WPA-PSK TKIP for working about 4h perfectly :-)
Last edited by redge on 2005-04-16 08:57, edited 1 time in total.
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
amn0270
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Post by amn0270 »

Actually I am running through a Belkin wireless router but the computer running WInVNC server is hard wired to the routers internal hub as is the the machine running the viewer. I am not using the wireless so the WLAN settings should not be related..[/quote]
Last edited by amn0270 on 2005-04-16 19:18, edited 1 time in total.
redge
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Post by redge »

I'm using version RC202 with both server and viewer
can you upgrade to RC20.5
http://www.uvnc.com/RC205

don't forget to restart computer after setup successfull

and try again
Last edited by redge on 2005-04-17 00:16, edited 2 times in total.
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
amn0270
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Post by amn0270 »

Already did the upgrade. Didn't help.
redge
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Post by redge »

read MSRC4 Plugin - Registry Version
http://home.comcast.net/~msrc4plugin/msrc4plugin.html
UltraVNC 1.0.9.6.1 (built 20110518)
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only experienced user, not developer
scovel
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Re: Winvnc server crashes when DSM plugin is used

Post by scovel »

Adam,
amn0270 wrote:When I use the DSM plugin, the server aka winvnc.exe crashes.
Can we get more details? Read the trouble-shooting section of my website. The batch (bat, cmd) files for debugging are in the plugin directory under UltraVNC. Copy them to the UltraVNC directory, and then use them to run the server and the viewer. Make sure to set "Log debug infos..." on the server.

Send me the 4 log files. RC4.log from the server, from the viewer, and vncviewer.log, and windvnc.log. Also, when the crash occurs, if you get any messages about the crash, write those down, or get a screen-shot.

Send all of that to the email address on my plugin website.

Sean
Guest

did you find a solution?? I'm having a similar issue

Post by Guest »

I just upgraded from RC18 to RC205. Everything seemed to install fine, but now I can't connect when I try using the DSM Plugin MSRC4Plugin. Everything worked great before the upgrade, now it gives me the error message on the client: Connection failed - Error reading Protocol Version

Possible causes:

-You've forgotten to select a DSMPlugin and the Server uses a DSMPlugin
-The selected DSMPlugin is not compatible with the one running on the Server
-The selected SDMPlugin is not correctly configured (also posisbly on the Server)
-The password you've possibly entered is incorrect

I have tried this is many different configurations between 3 machines. One is running Windows 98, one Windows XP, and one Server 2003. I have rebooted the Win98 & XP machines after installing (I can't reboot the server until the weekend), and I have tried connecting to the Server with the XP machine and I have tried connecting to the XP machine with both the server and the 98 machine. If I turn the plugin off, I can connect fine (still slow as the hook driver isn't working yet, but I can still connect), however, with the plugin turned on, it's crashing the vnc service on the server machine (either XP or 2003 Server) and the viewer machine is giving me the message listed above. Any help would be appreciated.

Thanks!!
scovel
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Post by scovel »

Details! Details!

Get me the log files like I requested of Adam (he never got back to me...) and any messages that pop up, and send them to my email address. I'll see what I can find.

Sean
mjdenham

Post by mjdenham »

Hi,

I had the error quoted at the start, then I realised I had the parental control s/w (Parental Filter) switched on - my client machine at home is also used by the kids.

Parental Filter blocks all sorts of things (which is good), but also stops vnc connecting to the server giving that unusual error message displayed at the start of this thread.

Regards

Martin
mjdenham

Post by mjdenham »

Sorry, by that unusual message I mean 'Connection failed Error reading Protocol Version'.

Sometimes Parental Filter allows me to the password dialog, but then the error 'WriteExact: Socket error while writing' occurs.

Not a bug, but it confused me for a while.
garretto

Same crash problem

Post by garretto »

Okay, i am having the same problem that adam has. I have a server and viewer on two computers. They are both version 1.0 . I can connect to computer 1 on computer 2 and computer 2 on computer one when I am not using the dsm plugin. However, when i use the dsm pluggin, the the viewer will just stop at the negotiating protocal thing and on the server, it will close and i'll get one of those windows error reporting windows. This happens on two computers remember. They are connected on a wireless b/g network. One computer has a g card and one has a b. However, encryption does work in one senario, with winvnc SC. I was expirimenting with SC and i turned on my viewer on one of my computers on listning mode and made the WinVNC SC connect with the dsm pluggin no_reg. So, is there a flaw or something with the server version 1.0 and the dsm pluggin?
HeadBeeGuy

Post by HeadBeeGuy »

I first encountered this problem today, and after some shotgun debugging, eventually figured out that it was happening every time when the RC4 plugin was outdated or mismatched between client/server.
Make sure you're using the most recent version of the RC4 plugin at both ends. To be certain, you might want to try copying the plugin from the "plugin" subdirectory to the main UVNC program directory (e.g. from c:\program files\ultravnc\plugin to c:\program files\ultravnc).
Even if you're really sure your plugin files are up to date, try it anyway; I was really sure I was up to date everywhere too, but in several places I found old RC4 plugins from replaced versions of UVNC still lurking in the main program dir and making a liar out of me. :wink:
Anyway, after clients/server were all on the same plugin version, everything connected buttery-smooth. Hope you have the same experience...good luck!
redge
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Post by redge »

please read twice FAQ DSMplugin on forum UltraVNC
[topic=3049][/topic]
UltraVNC 1.0.9.6.1 (built 20110518)
OS Win: xp home + vista business + 7 home
only experienced user, not developer
2manyhats

Post by 2manyhats »

I have seen this problem also. It only affects NT based machines. My workaround is to use the task scheduler. Perform a net stop an then seperately perform a net start on the (vnc server) machine 1 minute after bootup. You should be able to ge in at that point. It seems that the service needs to be restarted a 2nd time after bootup.

Kevin
Guest

Have same problem

Post by Guest »

and solved it with new beta DSM plugin

David
Mugatu

My mistake was the plugin location

Post by Mugatu »

My problem was that I had an old MSRC4Plugin.dsm in the UltraVNC folder. I copied the updated versions into the "plugin" folder, but it doesn't look there... I moved the files up to the main folder & now I'm connecting again. (Pretty silly.)
Zorlim
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Location: Helsinki, Finland
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Server OpenSSL Crash problem (UltraVNC / AESV2 RC3)

Post by Zorlim »

I also verfy that server crash problem. But in my case it says OpenSSL.DLL error at server side. After that connetions to server are accepted and password too. But then system hangs at negotiating protocol state.

After server is restarted then everything works again.

Any comments about this? I already connected AESV2 plugin author, but it seems that this is more generic problem.

It's always better to know if others encounter this problem or is just me. ;)

I unfortunately missed that error message and it's not too easy to repeat. Is there any easy way (not to recomplie) to enable debug logging for server and client?
Zorlim
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Re: Server OpenSSL Crash problem (UltraVNC / AESV2 RC3)

Post by Zorlim »

Better details w screencaps...

A) Server / OpenSSL trows error:

Image

B) Microsoft runtime crashes...

Image

C) After that clients are Unable to connect server.

Image

D) VNC Clients hang in negotiate protocol state. Even if you press cancel button process is left running.

Over all result seems quite poor... ;(

System Specialist - Zorlim - zorlim.net
Last edited by Zorlim on 2005-09-30 09:02, edited 1 time in total.
redge
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Post by redge »

Zorlim wrote:Is there any easy way (not to recomplie) to enable debug logging for server and client?
http://msrc4plugin.home.comcast.net/faq.html

and read Trouble-shooting
http://msrc4plugin.home.comcast.net/msr ... noreg.html
http://msrc4plugin.home.comcast.net/msrc4plugin.html

click and look topic below
[topic=4269][/topic]
UltraVNC 1.0.9.6.1 (built 20110518)
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Zorlim
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Post by Zorlim »

redge wrote: Trouble-shooting
http://msrc4plugin.home.comcast.net/msr ... noreg.html
http://msrc4plugin.home.comcast.net/msrc4plugin.html

click and look topic below
[topic=4269][/topic]
Thank you very many... I had terrible horry, so wondered that I managed to create those screenshots. Anyway, that OpenSSL error message seems pretty clear, so it should tell the location at the code which failed. I assume it's enough for start. Because I now know how to repeate that problem. I'll also create those logs and post those here too.

At least that kind of error message is enough in most of cases when I need to fix code which I have written my self.

Now generating logs. It seems that the problem isn't finding keyfiles it's something else.
Last edited by Zorlim on 2005-10-02 07:55, edited 2 times in total.
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