Added try block to check for null env
diff --git a/TestON/core/teston.py b/TestON/core/teston.py
index 9c2ebba..db17d8e 100644
--- a/TestON/core/teston.py
+++ b/TestON/core/teston.py
@@ -166,7 +166,10 @@
         driverObject = driverClass()
 
         if "OC" in self.componentDictionary[component]['host']:
-            self.componentDictionary[component]['host'] = os.environ[str( self.componentDictionary[component]['host'])]
+            try: 
+                self.componentDictionary[component]['host'] = os.environ[str( self.componentDictionary[component]['host'])]
+            except: 
+                self.log.error("Missing OC environment variable! Check your environment setup and retry") 
 
         connect_result = driverObject.connect(user_name = self.componentDictionary[component]['user'] if ('user' in self.componentDictionary[component].keys()) else getpass.getuser(),
                                               ip_address= self.componentDictionary[component]['host'] if ('host' in self.componentDictionary[component].keys()) else 'localhost',