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Sophos Email: "550 5.7.1 Command Rejected" error on outbound emails [Gateway mode] - Recommended Reads - Sophos Email - Sophos Community
![Mail from Plesk server is rejected with error: 550-5.7.1 is likely unsolicited mail – Plesk Help Center Mail from Plesk server is rejected with error: 550-5.7.1 is likely unsolicited mail – Plesk Help Center](https://support.plesk.com/hc/article_attachments/360029611174/mceclip0.png)
Mail from Plesk server is rejected with error: 550-5.7.1 is likely unsolicited mail – Plesk Help Center
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Email Error, 550 #5.7.1 Your access to submit messages to this e-mail system has been rejected - General Discussion - CyberPanel Community
![Exchange - SMTP error: 550 5.7.1 Client does not have permissions to send as this sender - SomoIT.net Exchange - SMTP error: 550 5.7.1 Client does not have permissions to send as this sender - SomoIT.net](https://somoit.net/wp-content/uploads/2017/02/Exchange-SMTP-error-550-5.7.1-Client-does-not-have-permissions-to-send-as-this-sender-2.jpg)
Exchange - SMTP error: 550 5.7.1 Client does not have permissions to send as this sender - SomoIT.net
![Email Error, 550 #5.7.1 Your access to submit messages to this e-mail system has been rejected - General Discussion - CyberPanel Community Email Error, 550 #5.7.1 Your access to submit messages to this e-mail system has been rejected - General Discussion - CyberPanel Community](https://community.cyberpanel.net/uploads/default/original/2X/e/efd55b7207be3ae332693cb8e5fb54591b3b41cc.png)
Email Error, 550 #5.7.1 Your access to submit messages to this e-mail system has been rejected - General Discussion - CyberPanel Community
![550-5.7.1 Unauthenticated email from yahoo.com is not is not accepted due to domain's 550-5.7.1 - Gmail Community 550-5.7.1 Unauthenticated email from yahoo.com is not is not accepted due to domain's 550-5.7.1 - Gmail Community](https://storage.googleapis.com/support-forums-api/attachment/thread-12927487-14212326409360197837.jpg)