How to block USB by GPO Server 2012

HOW TO BLOCK USB BY THE HELP OF GPO

PRESS WINDOW + R SHOWN BELOW

TYPE GPEDIT.MSC

NEW WINDOW IS OPEN LEFT SIDE  EXPAND THE USER CONFIGURATION AND GO FOR SYSTEM OPTION

 CLICK SYSTEM OPTION AND EXPAND IN RIGHT SIDE SETTING IS REMOVABLE STORAGE ACCESS EXPAND 

AFTER EXPAND THE REMOVAL STORAGE ACCESS NEW WINDOW IS SHOWN BELOW

THEN PRESS THE ALL REMOVAL STORAGE CLASSES DENY ALL ACCESS

PRESS RIGHT CLICK SELECT THE EDIT OPTION . SHOWN BELOW

BY DEFAULT NOT CONFIGURED OPTION IS ENABLE SO PRESS THE ENABLED OPTION  AND APPLY. OK

THEN PRESS WINDOW +R TYPE GPUPDATE

NEW WINDOW IS GROUP POLICY IS UPDATE LETS CHECK THE POLICY IS WORKING OR NOT ..