Ubuntu 12.04 allows the control of remote desktop i.e. another computer’s desktop using Remmina Remote Desktop Client. However, there is an issue taking control of the desktop using Unity. By default, Unity using all the 3D desktop and other jazzy effects. Therefore, although the screen is visible when connected, it does not refresh.
To overcome the issue, log in with the Unity 2D desktop. You can select Unity 2D by clicking on the Ubuntu icon just above your user ID on the login screen.
A patch is in the works, and should be available to users shortly.
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