An internal error occurred during: “Launching Project”. java.lang.NullPointerException

Question

My android project was compiling well but suddenly it stopped launching. Then I tried to launch other projects from Project Explorer and all project threw same exception:

Answer 1

One cause of this issue for me was that I had been updating my Android Tools with the installer. It was running in the background doing all its updates. I had forgotten about it since I had told it to do the work in the background. Then realized it had finished its work and needed a restart after the installation.

Once the upgrade / installation was done and the IDE was restarted, the Eclipse environment went back to behaving as normal.