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Download the License Removal Tool
Download the License Removal Tool from the Microsoft website for Mac.Run the Tool
Run the License Removal Tool on your Mac to clear all existing Office 365 license information.Re-sign into Office 365
Once the tool completes:Open any Office 365 application.
Sign back in with your Lehigh University credentials (username@lehigh.edu).
Activate Office 365
You should now be able to activate Office 365 and use the applications without further issues.