Update: UltraVNC 1.4.3.6 and UltraVNC SC 1.4.3.6: viewtopic.php?t=37885
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Encryption somehow linked to viewer's OS privileges?

Should you have problems with the DSM plugin, here's the place to look for help or report issues
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hg
Posts: 2
Joined: 2009-09-16 20:53

Encryption somehow linked to viewer's OS privileges?

Post by hg »

Ultra VNC SC works fine when the VNC viewer is executed with encryption (MSRC4Plugin.dsm) enabled:

Code: Select all

vncviewer.exe -dsmplugin MSRC4Plugin.dsm -listen 54321
Inbound requests w/o encryption are dropped, only encrypted requests make it to my desk. Perfect.
----------------------------------

Running the viewer w/o plugin

Code: Select all

vncviewer.exe -listen 54321
also works according to my expectations as long as I am logged on to Windows XP as a plain user: This time, encrypted inquiries are rejected, and non encrypted sessions are welcome. To my very surprise, logging on to XP as Admin or simply running the VNC Viewer with admin privileges ("run as") results in just the opposite: solely encrypted sessions are now granted while non-encrypted requests are denied. How come?

I tried to figure out where I miss the point, but I am stuck now. Maybe there is somebody out there who could give me a hand. Thanks

Here is the Host list I used for the testing (pls notice, dyndns changed for obvious reason):

Code: Select all

[HOST]
ENCRYPTED: WAN 2 Admin
-plugin -connect my.dyn.dns::54321 -noregistry
[HOST]
NON ENCRYPTED: WAN 2 Admin
-connect my.dyn.dns::54321 -noregistry
[HOST]
ENCRYPTED: LAN 2 Admin
-plugin -connect 127.0.0.1::54321 -noregistry
[HOST]
NON ENCRYPTED: LAN 2 Admin
-connect 127.0.0.1::54321 -noregistry

environment:
Windows XP Home SP3
VNCviewer 1.0.6.4
winVNC 1.0.0.18
YY
200
200
Posts: 996
Joined: 2006-11-13 15:11

Re: Encryption somehow linked to viewer's OS privileges?

Post by YY »

The vncviewer can save your setting in a setting file, so it may use the dsmplugin automatically even you havn't specified in the command line.

You may have been running the viewer with dsmplugin on AND saved setting as default.

Try if this can solve the problem:
1. Log on as Admin.
2. Run the VNCviewer, click the "delete saved setting" button at the bottom


Then re-run the test again. This should solve the problem
hg
Posts: 2
Joined: 2009-09-16 20:53

Re: Encryption somehow linked to viewer's OS privileges?

Post by hg »

You hit the bullseye!

I followed your steps and now U-VNC behaves as it is supposed to...
"You may have been running the viewer with dsmplugin on AND saved setting as default."
I've to admit that this was indeed the first thing I did when installing Ultra VNC recently!

Thanks a lot for your help, HG
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