I tried to add a new repository to software sources, but "add source" button is unavailable. I can't click on it.
I also tried to add a new software source from the terminal, but it didn't work.
sudo add-apt-repository ppa:n-muench/burg
sudo: command not found
I also tried these commands:
sudo add-apt-repository deb http://ppa.launchpad.net/n-muench/burg/ubuntu natty main
sudo: command not found
Best Answer
Open up the software center and go to Edit -> Software Sources menu. A popup window will open. Go to the Other Software tab and click the Add button at the bottom left corner. Copy/paste this line
ppa:n-muench/burg
in the APT line text box and click the Add Source button.See screenshot below:
In 18.04 and later open Ubuntu Software and select Software & Updates from the dropdown menu in the upper left corner of the desktop. A Software & Updates window will open. Select the Other Software tab, and click the Add button at the bottom left corner. Copy/paste this line
ppa:n-muench/burg
in the APT line text entry box as shown in the above screenshot and click the Add Source button.After that update your software sources by running this command in the terminal: