diff --git a/lib/index.js b/lib/index.js
index 88bc3ef1..fa384756 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -147,6 +147,6 @@ function HttpProxyMiddleware (context, opts) {
     var errorMessage = '[HPM] Error occurred while trying to proxy request %s from %s to %s (%s) (%s)'
     var errReference = 'https://nodejs.org/api/errors.html#errors_common_system_errors' // link to Node Common Systems Errors page
 
-    logger.error(errorMessage, req.url, hostname, target, err.code, errReference)
+    logger.error(errorMessage, req.url, hostname, target, err.code || err, errReference)
   }
 }