diff --git a/src/middlewared/middlewared/plugins/mail.py b/src/middlewared/middlewared/plugins/mail.py
index 31048fd4ef17c..c2b98ff39919e 100644
--- a/src/middlewared/middlewared/plugins/mail.py
+++ b/src/middlewared/middlewared/plugins/mail.py
@@ -156,7 +156,7 @@ async def do_update(self, data):
                 'This field is required when SMTP authentication is enabled',
             )
 
-        if not new['oauth']:
+        if not new['oauth'] or new['oauth']['provider'] == 'outlook':
             if not new['fromemail']:
                 verrors.add('mail_update.fromemail', 'This field is required')