Hi,

I was hoping that applying the command "/geometry/navigator/push_notify false" would stop the warnings like:

-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : GeomNav1002
      issued by : G4Navigator::ComputeStep()
Track stuck or not moving.
          Track stuck, not moving for 10 steps
          in volume -Ghost_line- at point (-0.1566291879234698,-0.1392259444973961,-0.0364690003991392) (local point (-0.001740324310260777,-0.001740323986794828,7.781011633711116e-05))
          direction: (-0.6034581158399398,-0.3119483130977905,0.7338436838880285) (local direction: (-0.6034581158399398,-0.3119483130977905,0.7338436838880285)).
          Potential geometry or navigation problem !
          Trying pushing it of 1e-07 mm ...Potential overlap in geometry!

*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------

But this is not the case. 

I took a look at the file "G4GeometryMessenger.cc": the previous command is allocated in the constructor (line 89) and there is the method "SetPushFlag" to apply it (line 327). But it is not present in if-checks in the method "SetNewValue" (line 213). To my understanding, this means the command is not applied. Either way, the warnings do not stop.

Adding the lines:

G4Navigator* navigator = G4TransportationManager::GetTransportationManager()->GetNavigatorForTracking();
  navigator->SetPushVerbosity(false);

in the method BeginOfRunAction() of my derived class solves the problem though.

Best Regards,
Thomas