Thanks for posting. I understand how frustrating it is when emails from a trusted sender never arrive, especially when they’re already added to Safe Recipients.
Just to confirm, are you using Outlook for Windows with a personal Outlook.com / Microsoft account, or is this a work/ school email account?
Have you already tried the Q&A Assist suggestions? If yes, what happened? In addition, please try the following:
If you’d like, please also share whether the sender is using a custom domain or a public email provider (no full addresses needed). That can help clarify whether this is likely rejection at the sending or receiving side.
Meanwhile, if this is a personal account, please try adding the sender as a contact, not just as a safe sender:
- Go to Outlook.com
- Select People > New contact
- Add the sender’s full email address and save
- Ask the sender to resend a test email
This can improve delivery reputation for personal accounts.
Please feel free to let me know how it goes. Thank you for your time and understanding.
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