diff --git a/src/calibre/devices/kobo/driver.py b/src/calibre/devices/kobo/driver.py
index 77da09149e..cdb9e0c4c9 100644
--- a/src/calibre/devices/kobo/driver.py
+++ b/src/calibre/devices/kobo/driver.py
@@ -852,7 +852,6 @@ class KOBO(USBMS):
                         if os.path.exists(fpath):
                             with open(cover, 'rb') as f:
                                 data = f.read()
-                            f.close()
 
                             # Return the data resized and in Grayscale if
                             # required