Hi @Espace.OM
Welcome to our forum!
To protect your domain details, we have removed some personal information from your post. In order to avoid privacy leakage, please remember to hide your personal information when you post next time.
In addition, here are a few steps you can take:
- Verify the Email Address: Double-check the recipient's email address for any typos or errors.
- Check Mailbox Status: Ensure that the recipient's mailbox is active and not full. You might need to contact the recipient to confirm this.
- Run Microsoft Support and Recovery Assistant: This tool can help diagnose and fix issues with your Microsoft 365 email account. You can download it here: Download and run Microsoft Support and Recovery Assistant.
- Check Email Rules and Forwarding Settings: Sometimes, email rules or forwarding settings can cause issues. Go to your email settings and review any rules or forwarding settings that might be affecting email delivery.
If all above do not work, you may want to refer to the article step-by-step for more inspiration.
Hope it helps!
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