diff --git a/trytond/trytond/convert.py b/trytond/trytond/convert.py
index e1e642369c..7162bdb558 100644
--- a/trytond/trytond/convert.py
+++ b/trytond/trytond/convert.py
@@ -795,6 +795,9 @@ def post_import(pool, module, to_delete):
 
     for mrec in mdata:
         model, db_id, fs_id = mrec.model, mrec.db_id, mrec.fs_id
+        if db_id is None:
+            mdata_delete.append(mrec)
+            continue
 
         logger.info('Deleting %s@%s from %s.%s', db_id, model, module, fs_id)
         try: