postmaster @outlook.com emails being attached to non spam emails

Question

For over several weeks now I have been getting these postmaster @outlook.com emails. They are saying "Delivery has failed to these recipients or groups: [Moderator note: Removed PII]@gmail.com." I have never forwarded or tried to send any emails to [Moderator note: Removed PII]@gmail.com. Not only am I getting these but they are attaching themselves to actual emails that are currently in my inbox. When I delete the postmaster @outlook.com emails, my original emails in my inbox also delete. I have tried blocking them, reporting them as junk, reporting them as phishing scams, and just deleting them. Nothing is working and I get over 26 of these type of emails a day. They are attaching to my current emails in my inbox and removing my them. What is happening. I need this to stop. I am losing important emails. I am also not getting normal emails I get because they are being attached to the postmaster @outlook.com, [Moderator note: Removed PII] @gmail.com email. I also went into my rules to see if some hacker added rules to my account allowing this to happen and there are no rules associated with my hotmail account.

Answer 1

Hi Krystn Smerecki

Please note that our forum is a public platform, and we will modify your question to hide your personal information in the description. Kindly ensure that you hide any personal or organizational information the next time you post an error or other details to protect personal data.  

I understand that you're facing spam-related delivery failure notices flooding your inbox and disrupting your legitimate emails.

The ******@outlook.com delivery failure messages (Non-Delivery Reports, or NDRs) referencing ******@gmail.com are very likely bounce notices generated from spam sent with your email address forged as the sender, a technique commonly known as email spoofing or "backscatter." Spammers do not need your password to do this. They simply place your address in the "From" field of junk mail sent to other recipients, and when those messages bounce, the NDRs are returned to you instead of the spammer. This is unfortunately a common occurrence and, by itself, does not indicate that your account has been compromised, which aligns with your finding that there are no unfamiliar rules configured in your account.

As for the NDRs appearing to "attach themselves to" and disappear along with your legitimate emails, this is most likely caused by Conversation View grouping messages together because they share the same or a similar subject line. When multiple messages, including NDRs, are grouped into a single conversation thread and that thread is deleted, all messages within it, including legitimate emails, are removed together.

Please try the following:

1, Turn off Conversation View in Outlook.com

• Go to Settings > Mail > Layout. Under Message organization, select "Do not group messages" instead of "Group messages by conversation."

This prevents legitimate emails from being bundled together with NDR messages, so deleting one will not remove the others.

2, Secure your account

• Go to: https://account.microsoft.com/security > Manage how I sign in
• Remove any unfamiliar sign‑in methods
• Check the list of devices associated with your account
• If you notice anything unusual, change to a strong password and Sign out everywhere
• Turn on Two-step verification: How to use two-step verification with your Microsoft account - Microsoft Support
• Check Recent activity: https://account.microsoft.com/activityand choose This wasn’t me/ Secure your account for anything you don’t recognize. For more details: What is the Recent activity page?

3, Continue reporting the messages as Phishing, not Junk

For the NDR messages themselves, "Report phishing" is the correct classification, and you mentioned that you have already been doing this. While reporting these messages helps improve Microsoft's filtering systems, it cannot prevent external mail servers from generating bounce messages for spoofed emails.

Note: None of the steps above will cause data loss. After disabling Conversation View, check your Deleted Items folder for any legitimate emails that may have been removed earlier. If the folder has not been emptied, those messages may still be recoverable.