Our emails are being rejected from IP 2a01:111:f403:2415::710

Hi @DLM   

Just checking in to see if there are any updates from your side. We'd really appreciate hearing how things are progressing! 

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Hi @DLM  

Is there any update from you? Let us know how things are going, your update would be greatly appreciated!    

Kind regards,   

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Hi @DLM 

Thank you for contacting Microsoft Support regarding the issue with email delivery from your IP address 2a01:111:f403:2415::710, which appears to be rejected by a recipient using Sophos Email Security. 

This type of rejection can occur for several reasons, including temporary filtering (greylisting), IP reputation concerns, or specific security policies configured on the recipient’s Sophos system. 

Here are a few steps you can try: 

1. Retry Sending the Email:  Sophos may be using greylisting, which temporarily rejects emails from unknown senders. Your mail server should automatically retry after a short delay. 
2. Check IP Reputation:  Use tools like MXToolbox or Talos Intelligence to verify if your IP is listed on any blocklists. If so, follow the instructions provided to request removal. 
3. Verify DNS Records:  Ensure your domain has valid SPF, DKIM, and DMARC records. These help establish trust and improve deliverability. 
4. Contact the Recipient:  Ask the recipient to check their Sophos Email Security logs and whitelist your IP if necessary. They may need to adjust their filtering rules to allow messages from your domain. 

If you need any assistance or have further questions, feel free to let me know. 

Warm regards, 

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