How to fix: mx.google.com rejected your message to the following email addresses

Question

I spent nearly two hours chatting with two different Microsoft agents trying to resolve this issue. Instead of providing a solution, they told me to look for alternatives and end the chat. This is highly unprofessional.

Any kind souls who can help on this issue. See error code below:

mx.google.com rejected your message to the following email addresses:

Your message couldn't be delivered because the recipient's email server (outside Office 365) suspected that your message was spam. To fix this, try to modify your message, or change how you're sending the message, using the guidance in this article: E-mailing Best Practices for Senders. Then resend your message. If you continue to experience the problem, contact the recipient by some other means (by phone, for example) and ask them to ask their email admin to add your email address or your domain name (the text after the "@" symbol in your email address) to their allowed senders list.

For Email Admins When Office 365 tried to send the message to the next email server outside of Office 365 the external email server returned the error below. This indicates the recipient's email server (or their email filtering service) suspected the sender's message is spam. If the sender isn't able to fix the problem by modifying their message then contact the recipient's email admin and ask them to add your domain name, or the sender's email address, to their list of allowed senders.

While the sender may be able to alter the message contents to fix this, it's likely that only the recipient's email admin can fix this problem. Unfortunately, Office 365 support is unlikely to be able to help fix these kinds of externally reported errors.

 

mx.google.com gave this error: Remote server returned message detected as spam -> 550 5.7.1 [2a01:111:f403:280c::801 19] Gmail has detected that this message;is likely suspicious due to the very low reputation of the sending;domain. To best protect our users from spam, the message has been;blocked. For more information, go to; https://support.google.com/mail/answer/188131 af79cd13be357-79bcf511f6fsi712489285a.66 - gsmtp

look for alternative

Answer 1

Hi @ Ian Yew

Welcome to our forum!

According to your description, the error occurs when you try to send emails to the recipient outside O365, does this issue occur when you send emails to other recipients?

I notice that you mentioned two different Microsoft agents, did you communicate directly with online Microsoft technical support?

And what is your account? An Exchange online account or something else?

In addition, for the error ‘550 5.7.1’,  i found that this error indicates a security setting in your organization or the recipient's organization is preventing your message from reaching the recipient. And Typically, you can't fix the problem yourself. You'll need the recipient or the recipient's email admin to fix the configuration on their end. If you are using an Exchange account, you may try the following steps, more information: Fix NDR error 550 5.7.1 in Exchange Online - Exchange | Microsoft Learn

Hope it helps!

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Answer 2

Hi Joan,

Yes, I managed to chat with the Microsoft Team.

I am unable to send emails to any Gmail accounts from my personal email address, xxxxxxxxxxxxx@outlook.sg. Could this be a domain-related issue?