Microsoft Outlook: Cannot send to Comcast email addresses from Microsoft Outlook domain email addresses

Question

• My office cannot send email to comcast.net addresses.
• We are using domain emails through Microsoft and GoDaddy.
• The problem first manifested 10/1/2024 and has not corrected intermittently--it has been a consistent problem.
• I tried to copy and paste a bounce-back email example, but the posting mechanism automatically deletes it. I have now removed all caps and bold faced font and hope this will post.

Thanks!

John

Answer 1

Hello

So this is a custom domain email address, right? If so, what's the email domain?

To share the bounce email, please make sure you redact any mentioning of private email addresses. Or share a screenshot instead, and edit to mask your private info.

Also, does it only happen when you send to Comcast, what about if you send to others, like gmail.com?

Answer 2

If your office is unable to send emails to Comcast addresses, there are a few potential issues to consider:

1. Blocked IP Address: It's possible that your organization's IP address has been blocked by Comcast due to spam detection. You can check if your IP address is on a blocklist using services like MXToolbox or WhatIsMyIPAddress. If it is blocked, you may need to contact Comcast to resolve the issue.
2. Email Configuration: Ensure that your email settings are correctly configured in Outlook. This includes verifying that the SMTP settings are correct and that your email account is set up to authenticate properly before sending emails.
3. Test Email: You can send a test email to a different domain to check if the issue is specific to Comcast. If emails to other domains are successful, this further indicates a problem with how Comcast is handling emails from your domain.
4. Check Bounce-back Messages: Although you mentioned issues with posting bounce-back messages, these can provide valuable information about why emails are not being delivered. If you can access these messages, look for specific error codes or messages that indicate the nature of the delivery failure.
5. Contact Support: If the problem persists, consider reaching out to Microsoft support or GoDaddy support for assistance, as they may have additional insights or solutions based on your specific configuration.

By following these steps, you should be able to diagnose and potentially resolve the issue with sending emails to Comcast addresses.

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