Applies ToOffice 2021 for Mac Office 2019 for Mac Microsoft 365 for home Office for business Office 365 Small Business Microsoft 365 for Mac

If you're trying to activate Microsoft 365 for Mac and receiving "Error Code: 0x8A010101," follow the steps below.

Sign in with your Microsoft Account.

  • Make sure you're using the correct Microsoft Account that is associated with your Microsoft 365 for Mac purchase.

  • Double check to make sure you're activating Office 2019 for Mac.

  • If you're accidentally trying to activate 2011 or 2016, uninstall and then download and install Office for Mac. You'll activate by signing in with your Microsoft account.

Select Sign In to activate Office for Mac

The sign in screen for Microsoft 365 for Mac should look something like this.

Still not working? Your Product Key may be invalid.

If you purchased your product key from anywhere other than an official Microsoft store or partner, your product key may be invalid.

Note: MSDN product keys are not valid for activating a retail Office suite.

To get the Microsoft 365 for Mac, you can subscribe to Microsoft 365 or buy a one-time purchase here.

Contact Support.

This article is updated based on your feedback. If you still need help activating Microsoft 365 for Mac, tell us about your issue in detail by leaving us a comment below.

You can also contact Microsoft support.

See Also

Download and install Office for Mac

Activate Office for Mac

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