PyQGIS Error using standalone script when loading a vector layer

Question

I've been able to execute the command below in the Python console in QGIS. I am able to execute from qgis.core import * and import qgis.utils with no errors in the OSGeo4W shell but adding the layer I am still getting QObject::connect: Cannot connect <null>::raiseError< QString > to QgsVectorLayer::raiseError< QString >

The script below works in the Python console within QGIS. My paths are set in Environment Variables as: PYTHONPATH=c:\OSGeo4W\apps\qgis\python and PATH=c:\OSGeo4W\apps\qgis\bin

from qgis.core import *
import gdal
import qgis.utils

QgsApplication.setPrefixPath("C:\\OSGeo4W\\apps\\qgis", True)
QgsApplication.initQgis()          
print QgsApplication.showSettings()

layer = QgsVectorLayer('/path/to/shapefile_folder/test.shp', 'test', 'ogr')

if not layer.isValid():
    print "Layer failed to load!"

else:
    print "Layer was loaded successfully!"

QgsMapLayerRegistry.instance().addMapLayer(layer)

Answer 1

from qgis.core import *

import gdal
import qgis.utils

QgsApplication.setPrefixPath("C:\OSGeo4W64\apps\qgis", True)

qgs = QgsApplication([], True)

qgs.initQgis()

print QgsApplication.showSettings()

layer = QgsVectorLayer('C:\Users\path to your shape\CB.shp', 'CB', 'ogr')

if not layer.isValid():

    print "Layer failed to load!"

else:

    print "Layer was loaded successfully!"

QgsMapLayerRegistry.instance().addMapLayer(layer)