Using New Outlook on Windows for personal email, calendar, and contact management
What you’re seeing is very likely email spoofing, not someone actually sending messages from inside your mailbox. The “from” address in email can be forged quite easily, and the extra “via q8idea.com / app.byrent.id / marians.de” is a clue that the sending server doesn’t match your real domain. Microsoft flags these as unverified because the authentication checks (SPF, DKIM, DMARC) don’t fully align.
This does not by itself mean your account is compromised. It usually just means someone is using your address as a fake sender, often for spam or phishing campaigns. That’s annoying but common, and it doesn’t require access to your account.
Deleting the emails and blocking the sender is fine for cleanup, but blocking often won’t stop spoofed messages because the sender address can keep changing. The more important question is whether there are any signs of actual account access. If you’re not seeing unfamiliar sent emails in your Sent folder, no unexpected login alerts, and no security notifications from Microsoft, that’s a good sign.
To be safe, you should still take a couple of precautions. Change your email password to a strong, unique one and make sure two-factor authentication is enabled on your Microsoft account. Then check your recent sign-in activity in your Microsoft account security page and look for any unfamiliar locations or devices. Also verify that there are no forwarding rules or inbox rules you didn’t create, since attackers sometimes add those if they get access.
If everything there looks normal, then this is almost certainly just spoofing and you don’t need to worry beyond basic hygiene. If you do see unknown logins or suspicious rules, then treat it as a compromise and secure the account immediately.
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hth
Marcin