diff --git a/lib/src/connector/score_connector.dart b/lib/src/connector/score_connector.dart
index 01a88800..98659a39 100644
--- a/lib/src/connector/score_connector.dart
+++ b/lib/src/connector/score_connector.dart
@@ -198,7 +198,7 @@ class ScoreConnector {
       return courseScoreList;
     } catch (e, stack) {
       Log.eWithStack(e.toString(), stack);
-      return null;
+      rethrow;
     }
   }
 
diff --git a/lib/src/task/score/score_rank_task.dart b/lib/src/task/score/score_rank_task.dart
index 5fe730ff..d8b0cf80 100644
--- a/lib/src/task/score/score_rank_task.dart
+++ b/lib/src/task/score/score_rank_task.dart
@@ -22,10 +22,10 @@ class ScoreRankTask extends ScoreSystemTask<List<SemesterCourseScoreJson>> {
         result = value;
         return TaskStatus.success;
       } catch (e) {
+        //TODO: generate strings for UI
         if (e is FormatException) {
-          return super.onError(R.current.getScoreRankError);
+          return super.onError("請先完成學期評量");
         } else {
-          //TODO: regenerate the string for this
           return super.onError("取得課表錯誤");
         }
       }