diff --git a/main.py b/main.py
index a60e395..d64fdfe 100644
--- a/main.py
+++ b/main.py
@@ -22,6 +22,7 @@ class SeafileUploader():
         self.uil = QUiLoader()
         self.loadSettings()
         self.pool = Pool(2)
+        self.seaf_client = None
         
     def showSettingsUI(self, parentWidget):
         self.parentWidget = parentWidget