Receive postmaster@outlook undeliverable

Question

Receiving postmaster@outlook undeliverable since signing up for Microsoft 365 basic

Answer 1

Hi Tom Wincek

Thanks for posting. I understand how confusing it can be to suddenly receive repeated ******@outlook.com undeliverable notices, especially after subscribing to Microsoft 365 Basic.

Please try the following:

1, Check for background sends from connected apps or devices

Sometimes undeliverable reports are triggered by apps or devices that continue sending mail automatically.

• Review any apps connected to your Microsoft account here: https://account.microsoft.com/privacy
• If you see apps you no longer use, remove them and monitor whether the postmaster messages stop.

2, Check sent messages that failed silently

Some undeliverable reports are delayed responses to earlier messages.

• Open “Sent Items”
• Look for messages marked as “Not delivered”
• If found, delete the draft and resend as a new message

Feel free to let me know how it goes and thank you for your understanding.

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Answer 2

Hello,can you please share the bounce email? It contains important diagnostic data that helps shed some light on the root cause. Feel free to redact personal information when you share.