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1. Log into the Azure Management Portal for your Office 365 tenant.
2. Go to the Azure Active Directory tab and select App Registrations.
3. Select "New Application Registration".
4. Give the application a name and keep the default selection of "Web App / API".
5. Enter a Sign-on URL (the value of this doesn’t really matter other than being unique) and click "Create".
6. Look for your new application on the Regitered Applications list and click access it.
7. Go to Settings.
8. Go to Required Permissions and click on "Add".
9. On the "Select an API" section, add the "Office 365 SharePoint Online" application
10. On "Select Permissions", select the following "Application Permissions":
    1. Read Managed Metadata.
    2. Have Full Control of all Site Collections.
    3. Read Items in all Site Collections. 
11. After saving you have to click "Grant Permissions" to apply the changes.

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