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I have TightVNC server on Windows Server 2008 and it breaks the connection right after the login. The same happens both on linux and windows clients:

Connected to RFB server, using protocol version 3.8
Enabling TightVNC protocol extensions
Performing standard VNC authentication
Authentication successful
vncviewer: VNC server closed connection

Anyone knows what is going on?

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I have this exact thing happen with TightVNC on the client and UltraVNC on the server. I haven't take the time to trouble-shoot yet. What's the VNC server being used? – sysadmin1138 Jul 29 '09 at 14:18
it's tightvnc server, not ultravnc – Drasko Jul 29 '09 at 14:51
up vote 1 down vote accepted

Maybe it is the manifestation of same problem described here:

Workaround to Run VNC Server in Windows Vista

The problems are caused by Windows Vista new security feature called Session 0 Isolation. Previous versions of Windows ran system services in the same login session as the locally logged-in user (Session 0). In Windows Vista, Session 0 is now reserved for these services, and all interactive logins are done in other sessions, causing VNC server unable to accept incoming remote control connection request.

and the proposed solution:

So in order to make VNC server on Windows Vista works properly, the workaround resolution (at least until the VNC developers to come out with proper fix or update to address the new security constraint in Windows Vista) is to run VNC server in user mode.

Or try if it works with UltraVNC.

P.S: Here is the MSDN article about Application Compatibility: Session 0 Isolation.

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are there security risks when running vnc in usermode, or is it more secure by not being at session 0? my gut says more secure, but not sure myself – Jimsmithkka Jul 13 '11 at 9:56

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