diff --git a/src/JBrowse/Store/SeqFeature/NCList.js b/src/JBrowse/Store/SeqFeature/NCList.js
index fbbd967c62..66cb9d95c7 100644
--- a/src/JBrowse/Store/SeqFeature/NCList.js
+++ b/src/JBrowse/Store/SeqFeature/NCList.js
@@ -86,7 +86,10 @@ return declare( SeqFeatureStore,
                       function(error) {
                           if( error.response.status == 404 ) {
                               thisB._handleTrackInfo( refData, {}, url );
-                          } else
+                          } else if( error.response.status != 200) {
+                              thisB._failAllDeferred( "Server returned an HTTP " + error.response.status + " error" );
+                          }
+                          else
                               thisB._failAllDeferred( error );
                       }
                     );