Delivery Failure

Question

I have a MSN email that whenever I try to send an email with an attachment from the outlook app i get this back. It works fine on web browser and I even signed into my email on someone else's computer and phone and it worked, just not working on mine. Here is the error code it sends back to me.

Delivery has failed to these recipients or groups:

(user) A problem occurred while delivering your message to this email address. Try sending your message again.

The following organization rejected your message: [PII]iphmx.com.

Diagnostic information for administrators:

Generating server: [PII]prod.outlook.com

(user) [PII]

Original message headers:

[PII : Removed]

rom: User <PII: removed]

Answer 1

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Hi Spencer Kelso

Please try these steps in order.

1) Recreate the message manually in the Outlook app

Do not reply to the old message, and do not select the recipient from the suggested/contact list.

Instead:

• Start a new email.
• Type the full recipient address manually.
• Attach the file again.
• Send the message.

If this works, the Outlook app may have been using a bad cached recipient entry.

2) Clear the recipient from AutoComplete

In the Outlook app:

• Start a new email.
• Begin typing the recipient’s address.
• When the suggested entry appears, select the X next to it to remove it.
• Type the full address again manually.

3) Test whether the attachment or message content is being rejected

From the same Outlook app on your computer, send three separate test messages to the same recipient:

• A plain text email with no attachment and no signature.
• The same email with the attachment added.
• The same email with the attachment replaced by a OneDrive sharing link.

If only the attachment version fails, the recipient’s server may be rejecting the attachment or message content. Please use OneDrive links instead of large attachments when message size or attachment delivery is a problem.

4) Check the From address in the Outlook app

In the Outlook app, open a new message and confirm that the From address is the same MSN address that works in the browser.

If you have more than one account or alias in Outlook, the app may be sending from a different account than Outlook on the web.

5) Remove and re-add the MSN account in the Outlook app

Since the same account works in a browser, on another computer, and on another phone, the issue may be local to this Outlook app profile.

Remove the MSN account from the Outlook app, restart Outlook, then add the account again using the automatic Microsoft account sign-in method.

6) Ask the recipient to check their mail filter or block list

The bounce says the message was rejected by the recipient’s organization/server. 550 5.1.0 can occur when the destination server does not accept messages from the sender or for the recipient, and Outlook.com delivery-failure guidance says recipient-side filters or blocklists may require the recipient’s provider to unblock the sender.

Ask the recipient to check:

• Their block list
• Junk/spam settings
• Mail rules or filters
• Whether their provider is blocking your MSN address

7) Use Outlook on the web as the workaround for now

Because sending works from the browser, use Outlook.com to send that attachment while troubleshooting the Outlook app on the affected computer.

If the issue continues, please reply with only these details:

• Are you using New Outlook, Classic Outlook, or the Outlook mobile app?
• Does the same attachment fail only to this recipient, or to all recipients?
• Does a plain email with no attachment send successfully from the Outlook app?
• Is the From address in the Outlook app the same MSN address that works in the browser?

Please tell me how it goes. If the problem persists, please don’t hesitate to reply to this thread and I will be happy to help. Have a lovely day!  

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