Problem with dependencies when installing ros-noetic
I remove ROS noetic and now I'm trying to reinstall ros-noetic on Ubuntu 20.04. I followed instructions in tutorial: http://wiki.ros.org/noetic/Installati... When I did it, I receive this error:
The following packages have unmet dependencies: ros-noetic-desktop-full:
Depends: ros-noetic-common-tutorials but it is not going to be installed
Depends: ros-noetic-joint-state-publisher-gui but it is not going to be installed
Depends: ros-noetic-robot but it is not going to be installed
Depends: ros-noetic-ros-tutorials but it is not going to be installed
Depends: ros-noetic-urdf-tutorial but it is not going to be installed Depends: ros-noetic-visualization-tutorials but it is not going to be installed
Depends: ros-noetic-viz but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
I tried to find solution and looked here and here, but it didn't work. What did I do wrong?
What does this mean? What happened?