In Microsoft Outlook, it can be challenging to determine if someone has blocked your email. Outlook does not provide direct notifications or error messages to indicate that your email has been blocked by the recipient. However, there are some signs that might suggest your email has been blocked:

1. No Delivery Receipt: If you typically receive delivery receipts when your email is delivered, and suddenly you stop receiving them for emails sent to a specific recipient, it could indicate that your emails are not reaching their inbox.
2. No Read Receipt: Similar to delivery receipts, if you used to receive read receipts when the recipient opened your emails, but you stop getting them, it might suggest that your emails are not being read.
3. No Response: If you regularly communicated with the person, and they suddenly stop responding to your emails without explanation, it could be an indication that they have blocked your emails.
4. Check the Sent Folder: Review your Sent Items folder in Outlook. If you see the emails you sent to the person, it suggests that your emails were sent successfully. However, if your emails do not appear in the Sent Items folder, there might be an issue with your email account or settings.
5. Try an Alternate Email Address: If you have an alternate email address (not used for spam or harassment), you can send a test email from that address to see if it gets through. If it does, it could mean that your primary email address is blocked.
6. Contact the Recipient: If you have a way to contact the person through other means (phone, social media, etc.), you can politely ask them if they have been receiving your emails or if there have been any issues with email communication.

It’s essential to note that there could be various reasons for communication issues, including technical problems, spam filters, or the recipient’s email settings. Jumping to conclusions about being blocked should be a last resort, and it’s always a good idea to explore other possibilities and maintain open and respectful communication with others.