I have a Mac and I have the same email address for both personal and business account

Hello @Sjlva PETROCCHI, 

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This issue likely happens because Microsoft Teams treats your personal and business accounts as separate identities, even if they share the same email address. Microsoft uses two identity systems:  

• Microsoft Account (MSA) > for personal services like Outlook.com, Xbox, Skype. 
• Azure Active Directory (AAD) > for work or school accounts in Microsoft 365. 

If you registered the same email address in both systems: 

• Your company created an AAD account for business use. 
• You (or someone) also created a personal Microsoft Account with the same email. 

So now, when you sign in, Microsoft asks: 

• “Work or school account” vs “Personal account” 
• They are completely separate identities, even though the email is identical. 

For your reference: What's the difference between a Microsoft account and a work or school account? - Microsoft Support 

Here are some steps you can try: 

Check Which Account You’re Using in Teams 

• Open Teams on your Mac. 
• Click your profile picture > Manage account. 
• Carefully confirm that: 
  • Whether you are signed in with your Work/School account or Personal account. If you have both, switch to the Work account for business meetings.  
  • The account you're creating meetings is a business account or a personal account. Teams calendar syncs with Outlook only for the work account, not the personal one. 

Use Outlook for Calendar Sync 

• Install Outlook for Mac (if not already installed). 
• Sign in with your business account (Microsoft 365 work account). 
• The Teams calendar syncs only with your work or school account, not with personal accounts. 

Or you can Open Outlook on the web: 

• Go to https://outlook.office.com 
• Navigate to File > Account Settings > Account Settings. 
• Confirm the default account is the same one used in Teams. 

Remove Duplicate Account in macOS 

• Go to System Settings > Internet Accounts. 
• If the same email is added twice (one as Exchange, one as Outlook), remove the duplicate. 
• Keep only the Exchange/Work account for calendar sync. 

If You Need Both Accounts 

Unfortunately, Microsoft does not allow merging personal and business accounts with the same email. The workaround is: 

• Use Teams desktop app for work. 
• Use Teams web app (https://teams.microsoft.com) for personal. 

Please understand that our initial response does not always resolve the issue immediately. However, with your help and more detailed information, we can work together to find a solution.    

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