https://www.lifewire.com/setup-ubuntu-remote-desktop-4129666

 

***** Enable Sharing On Ubuntu
1. Select the applications icon in the lower left of your screen.

2. In the Activities overview, search for Settings.

3. Launch the Ubuntu settings app.
4. Select Sharing from the left side menu.
5. On the Sharing tab, select Screen Sharing to bring up the options.
6.First, select Allow connections to control the screen, if it isn't already

7. Then, it's probably a good idea to select Require a password for a little bit of added security and to be able to sign in without accepting the connection on your Ubuntu PC.

8. When you're ready, flip the switch at the top of the window to enable screen sharing.

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***** Connecting to Your Ubuntu Desktop From Windows

1. To download RealVNC go to https://www.realvnc.com/en/connect/download/viewer/

2. Select the link to Download VNC Viewer.

3. After the download has finished click on the executable (called something like VNC-Viewer-6.0.2-Windows-64bit.exe). This file will be located in your downloads folder.

4. The first screen you will see is a license agreement Check the box to show you accept the terms and conditions, and press OK.

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Important points: DO NOT Login as Unity!!!

 

$ gsettings set org.gnome.Vino require-encryption false <== ubuntu security problem