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MSRC4Plugin and "Unknown Authentication Scheme" error

Should you have problems with the DSM plugin, here's the place to look for help or report issues
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andreaacme

MSRC4Plugin and "Unknown Authentication Scheme" er

Post by andreaacme »

Hi everybody, I couldn't find this error string in any posted topic so I have opened a new thread hoping that someone will be able to give me some answers.


<B>Config:</B>
UltraVNC v1.0.1 (used both on the server and on the client side)
UltraVNC Server is running in ServiceMode (not in ApplicationMode)
Server has MSRC4Plugin.dsm configured for encryption (Version 118)
Multi viewer connections option is set to "Keep existig connections"
Zip file for the plugin has been exploded in the C:....\UltraVNC\plugin DIR (couldn't see the plugins) and also in the C:....\UltraVNC DIR (plugins are now visible). Also the rc4.key file is in both directories.


<B>Problem:</B>

The problem is that I cannot connect at the first try and I receive an error message <i>"Unknown Authentication Scheme"</i> and the connections that were already active on the server drop (get instantly kicked out with no error).
At the second retry (with exact same parameters) it works if there aren't any new connections.


<B>Considerations:</B>

If I try to connect when I'm sure there are no active UltraVNC connections it works fine.
When I try to open the first connection and then I open another one (on the same server) it drops all the connections. This doesn't happen if I turn off the plugin (the encryption).


I truely think it is something to do with the plugin but I don't understand what's going on.

Please help and if you need more details, you only have to ask.



Regards,

Andy
scovel
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Post by scovel »

This is a limitation of the DSM architecture. With the plugin enabled you can only have one connection. Hopefully this will be fixed in UltraVNC soon.

Sean
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