Using Microsoft graph to read all users calendars
<p>I gave my application the following scopes:</p>

<pre><code>SCOPES = [ "Calendars.Read", "User.Read.All" ]
</code></pre>

<p>I got an access token.  With this token I am able to get the users and I get two users back which is correct.</p>

<p>When I then ask for the calendar of myself (admin):</p>

<pre><code>https://graph.microsoft.com/v1.0/users/stijn@temponia.onmicrosoft.com/calendarview?startDateTime=#{start_date.to_s}&amp;endDateTime=#{end_date.to_s}
</code></pre>

<p>This also works perfectly.  However when I do this for the other user:</p>

<pre><code>https://graph.microsoft.com/v1.0/users/frank@temponia.onmicrosoft.com/calendarview?startDateTime=#{start_date.to_s}&amp;endDateTime=#{end_date.to_s}
</code></pre>

<p>I get this error message:</p>

<pre><code>Access is denied. Check credentials and try again.
</code></pre>

<p>According to the documentation: <a href="https://graph.microsoft.io/en-us/docs/authorization/permission_scopes" rel="nofollow">https://graph.microsoft.io/en-us/docs/authorization/permission_scopes</a> </p>

<p><em>Calendars.Read:    Read calendars in all mailboxes:    Allows the app to read events of all calendars without a signed-in user.</em></p>

<p>The scope I got back together with the access token was this: "calendars.read user.read.all" so it got accepted.</p>

<p>What am I missing here?</p>