diff --git a/cfg_checker/common/exception.py b/cfg_checker/common/exception.py
index 8e8b818..52aab2d 100644
--- a/cfg_checker/common/exception.py
+++ b/cfg_checker/common/exception.py
@@ -31,3 +31,9 @@
     def __init__(self, message, *args, **kwargs):
         super(InvalidReturnException, self).__init__(message, *args, **kwargs)
         self.message = "# Unexpected return value: {}".format(message)
+
+
+class ErrorMappingException(CheckerException):
+    def __init__(self, message, *args, **kwargs):
+        super(ErrorMappingException, self).__init__(message, *args, **kwargs)
+        self.message = "# Unexpected error mapping/type: {}".format(message)