Register the Azure app for Exchange Online app in the Azure portal.
Log on to the Azure portal (https://portal.azure.com/) using your global admin user account.
Go to Azure Active Directory.
In the navigation pane, click App registrations.
The App registrations page appears.
Click New registration.
The Register an application screen appears.
In the Name box, type a name for the app.
Under Supported account types, select Accounts in this organizational directory only (tenant_prefix - Single tenant).
Copy and paste the following values in a document that you can access later:
You will enter these values in the Commvault software when you complete the Office 365 guided setup.