Hi @Dana - Alina Băetu ,
Can you successfully log in on the web? If so, the issue may be related to your client, try the following troubleshooting:
- In windows Settings > Accounts > Access work or school, remove the account and add it again and then log in to check the result.
- Update your Office to the latest version. Open any office application, click File > Office Account > Update Options > Update Now.
- Delete the old profile and create a new profile: go to Control Panel > Mail > Show Profiles, delete the old profile and create a new profile, set it as default profile, then re-add your account.
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