diff --git a/src/com/mirantis/mk/Gerrit.groovy b/src/com/mirantis/mk/Gerrit.groovy
index 5c5c575..bb6438e 100644
--- a/src/com/mirantis/mk/Gerrit.groovy
+++ b/src/com/mirantis/mk/Gerrit.groovy
@@ -97,8 +97,11 @@
             }
         }
         return true
+    }else{
+        def common = new com.mirantis.mk.Common()
+        common.errorMsg("Cannot perform gerrit checkout, given config file is not valid")
+        return false
     }
-    return false
 }
 /**
  * Execute git clone and checkout stage from gerrit review
@@ -136,9 +139,10 @@
 }
 
 def _validGerritConfig(LinkedHashMap config){
-    return config.get("gerritScheme","") != "" &&
-           config.get("gerritName","") != "" &&
-           config.get("gerritHost","") != "" &&
-           config.get("gerritPort","") != "" &&
-           config.get("gerritProject","") != ""
+    return config.get("gerritScheme","") != null && config.get("gerritScheme","") != "" &&
+           config.get("gerritName","") != null && config.get("gerritName","") != "" &&
+           config.get("gerritHost","") != null && config.get("gerritHost","") != "" &&
+           config.get("gerritPort","") != null && config.get("gerritPort","") != "" &&
+           config.get("gerritProject","") != null && config.get("gerritProject","") != "" &&
+           config.get("gerritRefSpec","") != null && config.get("gerritRefSpec","") != ""
 }
\ No newline at end of file