I have installed other packages, "LabView Interface For Arduino", "MakerHub Toolbox", "MakerHub Interface for Microsoft Kinect One" and "Mitsubishi Robotics Library", so I think VIPM is connected to internet. But when I tried to install the "Epson Robotics Library" there was again the Error Code 15:
Main Package Name: Epson Robotics Library v2.0.0.67
Package Name with Error: Epson Robotics Library v2.0.0.67
Error Message: VIPM could not install the package digimetrix_gmbh_lib_epson_robotics_library-2.0.0.67 .
Error Code: 15
Error Source: (Script VI could not be opened) 564907B357571B07D2F2