Tutorial 902 - Wrong object for picking - error
 

Hello,
in the last step of the Tutorial 902, when editing "Output Control", "Log file", you have to pick a monitoring location. Whenever I click on a cell or either of the both meshes I created, I get the error notification: "Wrong object for picking. Open the object from corresponding mesh in the viewer list." In the viewer list, everything else is greyed out, but the both meshes I can select don't work either.
Did anybody have this problem before and could help me?