Remote Desktop

[aldo]

My goal is to have a Linux virtual machine that can be used remotely (VNC or RDP or ) by several users simultaneously (less than 10).

I tried ubuntu 11.10 with xrdp and x11vnc server connecting from Windows with RDP, RealVNC Viewer and TightVNC viewer, with and without SSL.

The results are disappointing.
RealVNC returns "connection refused 10061".
TightVNC returns "failed to connect to server".
RDP connect but login failed (as shown in attachment).

My questions are:
- is there a step by step tutorial for incapable?
- is there is a virtual machine ready, or from which to start?

Thank you in advance for any help.