diff --git a/tubesync/common/errors.py b/tubesync/common/errors.py
index 9ff44a48..17ebec40 100644
--- a/tubesync/common/errors.py
+++ b/tubesync/common/errors.py
@@ -42,3 +42,8 @@ class DatabaseConnectionError(Exception):
         Raised when parsing or initially connecting to a database.
     '''
     pass
+
+
+class BgTaskWorkerError(Exception):
+    # Raised when the worker process is not in a normal working state.
+    pass