Update: UltraVNC 1.4.3.6 and UltraVNC SC 1.4.3.6: viewtopic.php?t=37885
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SC "Connection Failed - Invalid protocol!

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

SC "Connection Failed - Invalid protocol!

Post by DMSFinancial »

I used SC to create an executable that successfully connects to my support PC unencrypted. However, it will not connect to my support PC using the encrypted host and I get the following:

Connection Failed - Invalid protocol!
Possible Causes:

-You've forgotten to select a DSMPlugin and the Server uses a DMSPlugin
-Viewer and Server are not compatible.

Setup is a follows:
Prior to uploading the "custom.zip" file, I created a new rc4.key and inserted it into the zip file. I also copied the rc4.key file to the UVNC program folder and have the MSRC4Plugin_NoReg checked in the service properties. I have two "Hosts" listed in the helpdesk.txt file, one with and one without the "-plugin" command.

Please assist...Thanks
DMSFinancial

Reverse Connection w/ SC

Post by DMSFinancial »

I think I found my own answer...When using the the viewer in listening mode and using encryption, it appears as though you must use the "-dsmplugin" switch as follows:

"C:\program files\ultravnc\vncviewer.exe" -dsmplugin msrc4plugin_noreg.dsm -listen 5500
fijocha

Thank you!

Post by fijocha »

Thank you very much! You have saved me many hours of frustration! :-)
Charles, from Moncton', NB,Canada
olix
Posts: 7
Joined: 2006-01-17 17:48

Post by olix »

Thank you a lot because I forgotten to precise the complete path and your post helped me to start my plugin...

Thank you again,

Olivier, from France.
djgotee

protocal problem

Post by djgotee »

Thanks to whomever concieved such a wonderful program and again, thanks for posting this particular problem solved. I had this problem and was stupid enough not to know what caused it till I found this post, thanks again!
miles267
Posts: 2
Joined: 2007-11-19 02:37

Re: SC "Connection Failed - Invalid protocol!

Post by miles267 »

Hi, I too was receiving the Connection Failed - Invalid Protocol! message until I followed the steps you've outlined. However now I receive the following error:

Connection Failed - Error Reading Protocol Version
-You've forgotten to select a DSMPlugin and the Server uses a DSMPlugin
- The server DSMPlugin is not compatible with the one running on the Server
- The selected DSMPlugin is not correctly configured (also possibly on the Server)
- The password you've possibly entered is incorrect

Any idea what could be the problem. Doesn't seem any of these conditions apply to my setup since I followed the singleclick setup verbatim.

Thanks in advance.
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