C:\Users\Department\.qgis2\python\plugins\np>pyrcc4 -py2 resources.qrc -o resources.py
'pyrcc4' is not recognized as an internal or external command,
operable program or batch file.
How do I solve this problem?
You should use OSGEO Shell to run this command.
Go to Start Menu and search for OSGEO Shell, and then command prompt window will be open.
cd C:\Users\Department.qgis2\python\plugins\np> in the shell, and press enter.
It will set the current directory to the plugin directory.
Now run your pyrcc4 command.
You can also follow detailed tutorial here