diff --git a/price_update_notifications/wizard/send_price_update_notice.py b/price_update_notifications/wizard/send_price_update_notice.py
index 1675947..4d2f110 100644
--- a/price_update_notifications/wizard/send_price_update_notice.py
+++ b/price_update_notifications/wizard/send_price_update_notice.py
@@ -37,7 +37,7 @@ class SendPriceUpdateNotice(models.TransientModel):
                 warning_msg = None
             valid_partners = partners.filtered("email")
             if not valid_partners:
-                raise UserError(_("No valid partners were selected."))
+                raise UserError(_("No valid partners were selected. Partners must have an email address set."))
             vals.update(
                 partner_ids=partners.filtered("email").ids,
                 warning_msg=warning_msg,