Authorization_IdentityNotFound error MS Graph API

Question

Our application is going to do simple User.ReadBasic.All functions, which from what I understand do not require Admin permissions. Using the flow documented here: https://graph

Answer 1

which from what I understand do not require Admin permissions.

AFAIK,When using client credentials flow ,we need to set application permission to app , delegate permissions are used for delegated flow .

You could try below code to get users using ADAL :

        string authority = "https://login.microsoftonline.com/a703965c-e057-4bf6-bf74-1d7d82964996";
        AuthenticationContext authenticationContext = new AuthenticationContext(authority, false);
        var result= await authenticationContext.AcquireTokenAsync("https://graph.microsoft.com", new ClientCredential("clientid", "clientsecret"));


        string sURL = "https://graph.microsoft.com/v1.0/users";

        WebRequest request1 = WebRequest.Create(sURL);
        request1.Method = "GET";
        request1.Headers.Add("Authorization", "Bearer " + result.AccessToken);
        HttpWebResponse response1 = (HttpWebResponse)request1.GetResponse();
        if (response1.StatusCode == HttpStatusCode.OK)
        {
            // some code
        }

You could set "Read all users' full profiles" application permission for Microsfot Graph(for testing):