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I have been receiving this error message when trying to send emails to my clients:
Subject: xxxxxxxx
Remote Server returned: '601 Attempted to send the message to the following IPs: xx.xxx.xxx.xxx, xx.xxx.xxx.xxx'
Reporting-MTA: dns;gw03.site4now.net Final-Recipient: rfc822; ******@xx.xx Action: failed Status: 5.0.0
I am able to send and receive emails from certain people, but not my clients.
I do not have an admin console account with Microsoft 365 but I use outlook's app for Macbook.
Any help would be appreciated on dealing with this issue.
Using older versions of Outlook for Mac in business environments
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Hello Sylvie,
Welcome to Microsoft Community.
According to your description, seems this issue only occurs in your client, and this error message seems your IP gets blocked. Regarding this point, you might try to contact your client to contact their email provider to remove you from the IP blocked list.
Kind Regards,
Tommy