I am attempting to send an email via the Graph API (application not delegated).
I was given an app id, client secret, and tenant id. The app has Mail.Send permissions.
I have been testing via the Microsoft Graph Postman collection https://learn.microsoft.com/en-us/graph/use-postman. I had to add a new request based upon https://graph.microsoft.com/v1.0/me/sendMail for the application. I used https://graph.microsoft.com/v1.0/users/<sender's email>/sendMail.
I am able to get a token without issue, but when I attempt to invoke the sendMail endpoint I get the message that Access to OData is disabled. The person who set up the application for me has also tried to send email using a different application and was getting the same error.
Obviously, this is a permissions issue, but I have no idea what other permissions would be needed to just get a token and send email as a user. Does anyone have any idea what additional permissions would be needed? If not, can you point me in the right direction to find out which ones are needed?