Microsoft graph - listing emails - Access to OData is disabled

Question

I would like to use the Microsoft Graph API to programmatically check an Office365 Mailbox.

I followed all documentation, i.e.

• Created a app on Microsoft Identity Platform, with permissions Mail.Read, MailboxSettings.Read, User.Read.All - all with Admin Consent
• Created a secret code
• Created a mail-enabled security group including the email addresses that should be accessed by the script
• Created a ApplicationAccessPolicy to link those two items

Now,

• I can request an access token
• I can use this access token to get the list of users ( https://graph.microsoft.com/v1.0/users/ )
• But when I try to get the list of messages of a specific user ( https://graph.microsoft.com/v1.0/users/USERIDHERE/messages ) I get the following 403 error:

    {
      "error": {
        "code": "ErrorAccessDenied",
        "message": "Access to OData is disabled.",
        "innerError": {
          "request-id": "73db8b50-1f16-4301-abbd-d3fbbc78ca9b",
          "date": "2019-12-20T16:08:34"
        }
      }
    }

Answer 1

It actually solved itself, after waiting about 1 hour.

I guess the culprit was the Exchange cache.