Someone is sending emails through my Outlook account!!!!!

Good day Martim, and I’m sorry to hear that you’re going through this confusing situation with your work account. 

Just to gently clarify before we go any further, this is a user‑to‑user support forum. I don’t have the ability to access or investigate individual accounts because this is a user-to-user support forum. Moderators and contributors, including external Microsoft employees, do not have access to internal systems or the ability to directly take action on Microsoft product features. However, I truly hope I can help review your situation, offer some guidance, and support you in finding the right next steps as best as possible.   

Since the issue persists even after resetting your password and signing out of all devices, it is important to go through the full security process again to eliminate any remaining access points: 

Make sure your operating system, web browsers and Outlook app are fully updated to the latest version.    

Step 1: Ensure your device is clean and secure 

Open Windows Security by typing it into the search box next to the Start icon > Run a Quick scan first. 

If you still have concerns, run a Full scan or Microsoft Defender Offline scan. 

This will restart your device and check for deeper or persistent threats. 

Confirm that real time protection is enabled under Virus and threat protection settings.

If you still feel unsure about the device integrity, consider resetting the device completely. 

This step is critical because if malware or a keylogger is present, a new password can be exposed immediately after being entered. 

Step 2: Clear browser data and active sessions 

If you have accessed Outlook through a web browser: 

Open your browser settings > Clear all browsing data > Set the time range to All time. 

Ensure cookies, cache, and saved sessions are selected. 

Sign out of all accounts in the browser afterward. 

This helps remove any stored session tokens that might still allow access without requiring your password. 

Step 3: Strengthen your account security 

After cleaning your device and browser: 

• Sign in to your work account via My Sign-Ins | Sign-in activity | Microsoft.com 
• Change your password again. 

• After changing it, select the option to sign out of all sessions. 

Then update your security information: 

Go to Security info > Add multi-factor authentication methods such as: 

• Phone number. 
• Alternate email. 
• I truly recommend adding the Microsoft Authenticator app as a method. 

Review the existing methods. 

Remove any unfamiliar or suspicious entries only after adding your own methods to avoid losing access 

This ensures that even if someone attempts to sign in, they cannot proceed without your verification. 

Here are some important notes to keep in mind when using the Microsoft Authenticator method: 

• After adding the method, please test it to ensure you receive notifications properly. 
• If you want to change devices, first download the Microsoft Authenticator app on the new device. Then add a new method by selecting Microsoft Authenticator and follow the same setup process as you did on your previous device. 
• Once completed, test to confirm that you receive notifications on the new device. You can then remove the old device if desired. 
• After you add the method, please try test it to ensure you receive notification.  

Step 4: Check for unauthorized mailbox changes 

Open Outlook > Go to Settings > Email and carefully review your Inbox rules and forwarding settings. 

Delete any rules or forwarding addresses that you don't recognize. 

Step 5: Monitor and reach out your university's IT admin 

Continue monitoring your account activity closely. 

If you notice any further suspicious activity even after completing all steps above, I recommend contacting your university's IT administrator as soon as possible.  

They can take advanced actions such as revoking sessions, checking logs, or applying organization level protections. 

You may also share this reference with them for further guidance: Responding to a Compromised Email Account - Microsoft Defender for Office 365 | Microsoft Learn  

I truly hope these steps help you regain full control of your account and bring you peace of mind. If you have any updates or need further clarification at any point, please feel free to reach out again. I will be here to support you as best as I can. 

Thank you for your patience and understanding.  

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