diff --git a/src/calibre/db/restore.py b/src/calibre/db/restore.py
index c26f4dfe70..2c942cef1b 100644
--- a/src/calibre/db/restore.py
+++ b/src/calibre/db/restore.py
@@ -273,7 +273,7 @@ class Restore(Thread):
             os.rename(dbpath, save_path)
         except OSError as err:
             if getattr(err, 'winerror', None) == 32:  # ERROR_SHARING_VIOLATION
-                time.sleep(4)  # Wait a little for dropbox or the antivirus or whatever to release the file
+                time.sleep(30)  # Wait a little for dropbox or the antivirus or whatever to release the file
                 os.rename(dbpath, save_path)
             else:
                 raise