I am currently trying to make REST calls to get mailbox message stats for a particular account (i.e. read/unread count). I have done this in the Microsoft Graph Explorer and have managed to get the relevant User.Read and many other non-admin permissions.
When I try to replicate this process in Postman, I get "Access is denied. Check credentials and try again.". I followed this guide right until here where I can't move forward despite the correct permissions.
Even my token generation response contains the "scope": "User.Read"
I just want to make a call to GET https://graph.microsoft.com/v1.0/me/messages
The registered app is the account of the email I am trying to monitor. I can make this call successfully Graph Explorer, but I am unable to replicate the results with Postman, PowerShell, or groovy
It turned out Delegated Permissions weren't enough, despite the fact that it was what I understood my circumstance. It only started working after I gave it APP Permissions