Could not open X display giggle: Cannot open display

I'm completely new to Linux, I have installed in my computer (running on windows 7) a Virtual machine with Ubuntu desktop 14.04. I have installed some programs using apt-get install NAME_OF_THE PROGRAM. The problem is that when I try to launch the GUI of these programs from a terminal, I'm always getting problems and I don't get to have the programs working. Now I have installed Giggle, the installation was ok but if I try to run giggle from the terminal I get:

** (giggle:8581): WARNING **: Could not open X display giggle: Cannot open display:

And this problem is for all the programs that I install.

For example if I try to run xhost I get:

xhost: unable to open display "localhost:0"

What is the next step to fix these problems??

Any help or recommendation would be really appreciated.

1 Answer

Run the following command from your terminal to fix this:

sudo service lightdm start
export DISPLAY=:0.0

LightDM is the display manager running in Ubuntu, the first command starts this service. The second command sets the value in DISPLAY variable for exporting display on the client.