diff --git a/chaos_monkey/__init__.py b/chaos_monkey/__init__.py
deleted file mode 100644
index 05a457b0cee..00000000000
--- a/chaos_monkey/__init__.py
+++ /dev/null
@@ -1 +0,0 @@
-__author__ = 'itamar'
diff --git a/chaos_monkey/config.py b/chaos_monkey/config.py
index addb9fd54b4..b26c911b06e 100644
--- a/chaos_monkey/config.py
+++ b/chaos_monkey/config.py
@@ -45,6 +45,11 @@ def _cast_by_example(value, example):
 
 class Configuration(object):
     def from_dict(self, data):
+        """
+        Get a dict of config variables, set known variables as attributes on self.
+        Return dict of unknown variables encountered.
+        """
+        unknown_variables = {}
         for key, value in data.items():
             if key.startswith('_'):
                 continue
@@ -55,9 +60,11 @@ def from_dict(self, data):
             try:
                 default_value = getattr(Configuration, key)
             except AttributeError:
-                raise
+                unknown_variables[key] = value
+                continue
 
             setattr(self, key, _cast_by_example(value, default_value))
+        return unknown_variables
 
     def as_dict(self):
         result = {}
diff --git a/chaos_monkey/control.py b/chaos_monkey/control.py
index f8f3e3ee01d..cdeb47a766c 100644
--- a/chaos_monkey/control.py
+++ b/chaos_monkey/control.py
@@ -124,7 +124,7 @@ def load_control_config():
             return
 
         try:
-            WormConfiguration.from_dict(reply.json().get('config'))
+            unknown_variables = WormConfiguration.from_dict(reply.json().get('config'))
             LOG.info("New configuration was loaded from server: %r" % (WormConfiguration.as_dict(),))
         except Exception, exc:
             # we don't continue with default conf here because it might be dangerous
@@ -132,6 +132,23 @@ def load_control_config():
                       WormConfiguration.current_server, reply._content, exc)
             raise Exception("Couldn't load from from server's configuration, aborting. %s" % exc)
 
+        if unknown_variables:
+            ControlClient.send_config_error()
+
+    @staticmethod
+    def send_config_error():
+        if not WormConfiguration.current_server:
+            return
+        try:
+            requests.patch("https://%s/api/monkey/%s" % (WormConfiguration.current_server, GUID),
+                                data=json.dumps({'config_error': True}),
+                                headers={'content-type': 'application/json'},
+                                verify=False,
+                                proxies=ControlClient.proxies)
+        except Exception, exc:
+            LOG.warn("Error connecting to control server %s: %s", WormConfiguration.current_server, exc)
+            return {}
+
     @staticmethod
     def check_for_stop():
         ControlClient.load_control_config()
diff --git a/chaos_monkey/requirements.txt b/chaos_monkey/requirements.txt
index 8c77333f9e2..34f24c78f1d 100644
--- a/chaos_monkey/requirements.txt
+++ b/chaos_monkey/requirements.txt
@@ -12,3 +12,5 @@ psutil
 PyInstaller
 ecdsa
 netifaces
+mock
+nose
diff --git a/monkey_island/cc/main.py b/monkey_island/cc/main.py
index ccf3fe995eb..b05c42e7044 100644
--- a/monkey_island/cc/main.py
+++ b/monkey_island/cc/main.py
@@ -86,6 +86,8 @@ def patch(self, guid):
             update['$set']['config'] = monkey_json['config']
         if 'tunnel' in monkey_json:
             update['$set']['tunnel'] = monkey_json['tunnel']
+        if 'config_error' in monkey_json:
+            update['$set']['config_error'] = monkey_json['config_error']
 
         return mongo.db.monkey.update({"guid": guid}, update, upsert=False)