Using Classic Outlook on Windows for personal email, calendar, and contact management
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Hi Bonnie L. Lane,
I understand how disruptive this was, especially when you were trying to send a time-sensitive and legitimate message to another board member.
An Undeliverable notice stating that a message was identified as spam does not necessarily mean that the message was actually spam or that your account has been permanently marked as a spam account. It means that the message triggered an automated filtering check. This can sometimes happen when similar messages are sent repeatedly or to several recipients within a short period, or when certain links or other elements in the message are flagged.
To narrow down the cause, please open one of the delivery-failure messages, scroll to Diagnostic information for administrators, and let me know the complete error code shown there, such as 533 5.4.0 or 550 5.7.x. Please remove any email addresses or other personal information before posting it publicly. Also, before the issue began, had you sent the same or a similar message to several recipients within a short period?
In the meantime, please try the following:
- Sign in directly at Outlook.com and send a short test message containing plain text only.
- Temporarily remove the Facebook URL, signature, images, and attachments, then test again.
- Manually type the recipient’s full address instead of selecting it from Outlook’s Auto-Complete list.
- Check your Microsoft account’s recent activity and Sent Items for anything unfamiliar, since unusual account activity can sometimes affect sending.
- If the plain-text message works, add the original content back gradually to identify what is triggering the filter.
You can also review Microsoft’s guidance for failed delivery messages.
If the same error occurs in both Classic Outlook and Outlook.com, even with a simple plain-text message, the issue may require account-level review. Please contact Microsoft Support, describe the problem as “My legitimate Outlook.com messages are being returned as undeliverable and identified as spam”, and provide the complete error code from the delivery report. If the Support Assistant appears, enter “I need to speak with a live support agent about an Outlook.com email delivery issue.”
Please note that this is a user-to-user support forum. Contributors here cannot access your account, review the server-side filtering decision, or remove a sending restriction directly. Thank you so much for your understanding.
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