Mremoteng: Real VNC v5.3.2

Created on 7 Apr 2017 · 8Comments · Source: mRemoteNG/mRemoteNG

Will there be any support for RealVNC v5.3.2 server connections? When connecting to a workstation that is running this version of the RealVNC server, this error pops up...

07-Apr-2017 2:53:55 PM
Opening connection failed!
Unable to connect to the server. Error was: Only versions 3.3, 3.7, and 3.8 of the RFB Protocol are supported.
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ErrorMsg
06-Apr-2017 3:18:11 PM
Opening connection failed!
Unable to connect to the server. Error was: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 10.120.50.186:5900

I assume mremoteng is only capable of connecting to VNC versions of 3.8 or earlier.

Are there any future plans to allow connection to higher versions of VNC?

Thanks for your help!

_Operating system: Windows 7 x64
mRemoteNG version: 1.75.7000.19194_

Enhancement VNC VendoUpstream Issue

Source

CHADOKI

Most helpful comment

Since the upstream repo has been archived, I would rather abandon VncSharp in favor of something else since I would rather that we focus on mRemoteNG bugs/features rather than attempting to build/fix/update/enhance a VNC client.

We may be able to integrate a VNC viewer into mRemoteNG, however that may require customization like we do with PuTTYNG.

TightVNC offers a Viewer SDK that they license commercially: https://www.tightvnc.com/licensing-dotnetviewersdk.php

That would be the best solution, but is likely cost prohibitive and I would prefer to stick to fully FLOSS solutions if possible. Using the TightVNC viewer integrated in may be a possibility though (it's GPL so we shouldn't run afoul of the .NET SDK license at all - thought they might not appreciate the fact that we're working around their revenue stream). TigerVNC and UltraVNC are other options that are GPL, but I'm not sure if they handle new RFB versions...

kmscode on 2 Apr 2019

🎉2 👍1

All 8 comments

We would like to be able to support higher version, however any version of the RFB protocol over 3.8 (such as the version used by RealVNC) are proprietary. Licensing the use of the newer protocols may be cost-prohibitive - though it has been a while since I checked into it

sparerd on 7 Apr 2017

👍1

ahh ok.... that makes sense. thank you for the info. would be nice, hopefully the proprietary restrictions have changed... Please let me know if you find out...
thanks

CHADOKI on 7 Apr 2017

I have computer with RealVNC server and cannot downgrade it but is did change ProtocalVersion to 3.8 so i can use Mremot but now i get this error. Anyone?

ErrorMsg
10/19/2017 3:04:06 PM
Opening connection failed!
Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.

gunnarh79 on 19 Oct 2017

I chanhed the Protocol Version to 3.3. Now it works.

pxlcore on 16 Jan 2019

TIghtVNC (open source) does support at least some of these versions

f-scholer on 1 Apr 2019

It looks like in TightVNC 2.7.1 they added the ability to connect to servers running RFB 4.0+. My guess is they just lie to the server about which protocol version they will use. They tell the server they support protocol 4.0 or something to get through the connection handshake then just use 3.8 in the background. Would be interesting to know if Vncsharp (the library we use) could do the same thing.

@kmscode thoughts?

sparerd on 1 Apr 2019

👍1

We may be able to integrate a VNC viewer into mRemoteNG, however that may require customization like we do with PuTTYNG.

TightVNC offers a Viewer SDK that they license commercially: https://www.tightvnc.com/licensing-dotnetviewersdk.php

kmscode on 2 Apr 2019

🎉2 👍1

Its probably not the answer you want to hear, but this worked for me.

https://www.instructables.com/id/Raspberry-Pi-Remote-Desktop-Connection/

it worked with mRemoteNG too.