diff --git a/addons/account/models/account_journal.py b/addons/account/models/account_journal.py
index 90b96b79471..640741b5665 100644
--- a/addons/account/models/account_journal.py
+++ b/addons/account/models/account_journal.py
@@ -708,7 +708,6 @@ class AccountJournal(models.Model):
         invoices = self.env['account.move']
         with invoices._disable_discount_precision():
             for attachment in attachments:
-                attachment.write({'res_model': 'mail.compose.message'})
                 decoders = self.env['account.move']._get_create_document_from_attachment_decoders()
                 invoice = False
                 for decoder in sorted(decoders, key=lambda d: d[0]):