diff --git a/src/DIRAC/Core/DISET/TransferClient.py b/src/DIRAC/Core/DISET/TransferClient.py
index 0791d4027cb..b9a37623950 100755
--- a/src/DIRAC/Core/DISET/TransferClient.py
+++ b/src/DIRAC/Core/DISET/TransferClient.py
@@ -71,6 +71,7 @@ def sendFile(self, filename, fileId, token=""):
             retVal = transport.receiveData()
             return retVal
         finally:
+            fileHelper.oFile.close()
             self._disconnect(trid)
 
     def receiveFile(self, filename, fileId, token=""):