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Using your default web browser, open the Microsoft 365 login page: https://portal.office.com
Info title Important If you are already signed in with another Microsoft 365 Account, click on your profil icon and choose Sign in with a different account
Log in with your OST account access data, which you received in the Welcome to OST e-mail to your private e-mail address
Choose Next, install the Microsoft Authenticator app on your smartphone and then choose Next on your browser
(alternatively
)UI Expand title Alternatively you can set up SMS as default method 
- Open the Microsoft Authenticator app, click the plus
, choose Work or school account, then Scan QR-Code, choose Next on your browser
- Scan the QR-Code in your browser with your smartphone, the OST-Account will be added to the app and has to approved
- Multifactor authentication has been successfully set up, click Next and then Done
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