When you launch it type your hda server name followed by a colon and the number 1 (this is the name you gave it when you installed Ubuntu)for example: Ubuntu-1204:1

Or use it's static ip address and :1 eg: 192.168.1.55:1 in the VNCServer box.

Then click Connect, enter the password you created when you typed after installing vncserver.

You now see the desktop screen.

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