Hi,
I have the following error on Windows XP SP3
Connection Failed - invalid Protocol
Posibles causes:
-You´ve forgontten to select a DSMPluggin and the server uses a DSMPluggin
- Viewer and Server are not compatible (they use diferrent RFB Protocol).
I put in CS folder and in the Support folder the same DSMPluggin and the same rc4.key!
Some help please,
Thanks,
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Feedback is welcome
A new stable version, UltraVNC 1.6.4.0 and UltraVNC SC 1.6.4.0 have been released: https://forum.uvnc.com/viewtopic.php?t=38095
Feedback is always welcome
2025-12-14: 1.7.1.X-dev release builds need tests and feedback: https://forum.uvnc.com/viewtopic.php?t=38134
2025-12-02: We need help: English Wikipedia UltraVNC page has been requested to deletion: https://forum.uvnc.com/viewtopic.php?t=38127
Any help is welcome to improve the UltraVNC page and/or to comment on the Wikipedia Talk page
2025-05-06: Forum password change request: https://forum.uvnc.com/viewtopic.php?t=38078
2023-09-21: Important: Please update to latest version before to create a reply, a topic or an issue: https://forum.uvnc.com/viewtopic.php?t=37864
Development: UltraVNC development is always here... Any help is welcome
Feedback is welcome
Connection Failed - invalid Protocol
Re: Connection Failed - invalid Protocol
Make sure your are using the compatible DSMPluggin at both end. Version 1.1.x and 1.2.x are not compatible. See the thread [topic=12187]SC with MSRC4Plugin --> "Buffer to big"[/topic] for detail.mloureiro wrote:I put in CS folder and in the Support folder the same DSMPluggin and the same rc4.key!

