How did you install Geant4 and with what options (and which version of Ubuntu is this?)? Also, could you post the full output from running the example please (copy paste is fine, and in fact more helpful than a screenshot)?
How did you install Geant4 and with what options (and which version of Ubuntu is this?)? Also, could you post the full output from running the example please (copy paste is fine, and in fact more helpful than a screenshot)?