Granting consent for an individual user
During the connection set up process, you will be presented with a permission consent screen. The checkbox is only seen when when signed into an admin account, checking it grants organization-wide consent.
Granting consent for all users in your domain
Logged in as an administrator for your Microsoft 365 domain, go to Azure > Enterprise applications and find the app you want to grant consent to, for example, Enterprise Mail Handler (JEMHC)
Select the app and then go to the Permissions page
Here you will see a button that allows an admin to grant consent for the app for all users
Revoking user granted consent to an app
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Logged in as an administrator for your Microsoft 365 domain, go to Azure > Enterprise applications and find the app you want to revoke consent from, for example, Enterprise Mail Handler (JEMHC)
Select the app and then go to the Permissions page.
Here you can see permissions granted by admins. Revoke permission consents as required.