O365 | Not able to receive emails

[Joao Casqueiro]

Hi

I have just been added as an admin for a O365 tenant and noticed that:

* The domain (re-food.org) is listed and I am able to create users

* I am able to send email from user@re-food.org but but I am not able to receive email from users outside the organization.

I assume this has something to do with mxrecords but I am not able to troubleshoot it and find out how to correct it.

Can anyone help?

The error that I receive when trying to send emails to this domain is below.

Thanks/Brgds 

------

From: Microsoft Outlook <postmaster@outlook.com>
Sent: 17 de maio de 2020 10:14
To: joaocasq@hotmail.com
Subject: Undeliverable: Teste

vps.oceanlab.net rejected your message to the following email addresses:

User1 (user1@re-food.org)
Your message couldn't be delivered. When Office 365 tried to send the message, the external email server returned the error below. This is probably due to a problem or policy setting on the recipient's email system.

Check the error for information about the problem. The error might tell you what went wrong and how to fix it. For example, if it says the message was blocked due to a potential virus, try sending the message again without attachments.

For Email Admins
This error was reported by an email server outside Office 365, and if the sender is unable to fix the problem by modifying their message then it's likely that it's a problem that only the recipient's email admin can fix.

1. Check the error for information about the problem. The error might tell you what went wrong and provide clues for how to fix it. For example, if it says the message was rejected due a Sender Policy Framework (SPF) issue then you'll have to work with your domain registrar to properly configure your SPF record.

1. Check the error for information about where the problem is happening. For example, look for a domain name like contoso.com. This tells you which organization was responsible for the error. The recipient's email server could be causing the problem, or it could be due to a third-party service that your organization or the recipient's organization is using to process or filter email messages.

1. If you can't fix the problem, contact the responsible party's email admin. This could be the recipient's email admin, your smart host service admin, or someone similar. Provide them with the error code and error message from this non-delivery report (NDR) to help them troubleshoot the issue.

Unfortunately, Office 365 support is unlikely to be able to help with these kinds of externally reported errors.

vps.oceanlab.net gave this error:
Remote server returned an error -> 550 No such person at this address"

User2 (user2@re-food.org)
Your message couldn't be delivered. When Office 365 tried to send the message, the external email server returned the error below. This is probably due to a problem or policy setting on the recipient's email system.

Check the error for information about the problem. The error might tell you what went wrong and how to fix it. For example, if it says the message was blocked due to a potential virus, try sending the message again without attachments.

For Email Admins
This error was reported by an email server outside Office 365, and if the sender is unable to fix the problem by modifying their message then it's likely that it's a problem that only the recipient's email admin can fix.

1. Check the error for information about the problem. The error might tell you what went wrong and provide clues for how to fix it. For example, if it says the message was rejected due a Sender Policy Framework (SPF) issue then you'll have to work with your domain registrar to properly configure your SPF record.

1. Check the error for information about where the problem is happening. For example, look for a domain name like contoso.com. This tells you which organization was responsible for the error. The recipient's email server could be causing the problem, or it could be due to a third-party service that your organization or the recipient's organization is using to process or filter email messages.

1. If you can't fix the problem, contact the responsible party's email admin. This could be the recipient's email admin, your smart host service admin, or someone similar. Provide them with the error code and error message from this non-delivery report (NDR) to help them troubleshoot the issue.

Unfortunately, Office 365 support is unlikely to be able to help with these kinds of externally reported errors.

vps.oceanlab.net gave this error:
Remote server returned an error -> 550 No such person at this address"

[#2 · Accepted solution]

@Joao Casqueiro 

Your MX record is currently pointed to;

This is obviously not Office 365.  To find out the MX record you require to route your emails to O365, you need to click on the domain in the M365 admin center at https://admin,microsoft.com and click on Settings >  Domains.  Choose your domain in the list and then click Check DNS.  Here you will find the required MX and other DNS records which are required for your domain to enable functionality in M365, and you will see which records are present and correct, and which are missing and need to be added.

Please be sure that you don't need to leave the MX records as they are for any reason though.  MX records are not to be changed lightly.

[#3]

I have a quick check on your DNS records on whatsmydns and I saw that it is not pointing to Microsoft 365.

Update your DNS records at your hosting provider or you can follow this articles too ->
https://docs.microsoft.com/en-us/microsoft-365/admin/get-help-with-domains/information-for-dns-recor...

https://docs.microsoft.com/en-us/microsoft-365/admin/get-help-with-domains/create-dns-records-at-any...

[#4]

Gerv is correct. Unless you using something like mimecast for extra protection then you need to have the mx record pointing to mimecast instead.

You also need to check that your spf record has the correct sending IPs /or domains in it. For office 365 that is normally

include:spf.protection.outlook.com


other record you need are

Record Type Host Points to TTL
CNAME (Alias) autodiscover autodiscover.outlook.com 1 hour
CNAME (Alias) lyncdiscover webdir.online.lync.com 1 hour
CNAME (Alias) sip sipdir.online.lync.com 1 hour

and

Record Type Name Target Protocol Service Priority Weight Port TTL
SRV (Service) @ sipdir.online.lync.com _tls _sip 100 1 443 1 hour
SRV (Service) @ sipfed.online.lync.com _tcp _sipfederationtls 100 1 5061 1 hour