Sending, receiving, and organizing email in Outlook.com
Hi @Chanathip
I understand how frustrating it is to keep receiving these suspicious messages. Since the displayed sender address can be spoofed, blocking only the address shown in the From field may not stop similar emails.
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You can view the message headers in Outlook.com to check the actual sending address or domain, then create an Inbox rule using a consistent value found in the messages, such as part of the sender address or subject, and move matching emails to Junk Email or Deleted Items. Please review the rule carefully to avoid filtering legitimate messages. View internet message headers in Outlook
Also, do not open or preview the unexpected PDF or configuration attachments. Select each suspicious message and choose Report > Report phishing so that it is submitted to Microsoft for analysis. Reporting phishing removes the message and helps improve filtering, but it does not automatically block the sender.
Please feel free to let me know if you have any further updates, thanks.
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