title: Discard hidden folders with Outlook REST Api
body: <p>When retrieving folders list with <a href="https://msdn.microsoft.com/en-us/office/office365/api/mail-rest-operations" rel="nofollow">Outlook REST API</a> (beta endpoint)</p>
  
  <blockquote>
    <p><a href="https://outlook.office365.com/api/beta/me/MailFolders" rel="nofollow">https://outlook.office365.com/api/beta/me/MailFolders</a></p>
  </blockquote>
  
  <p>I get the complete list of folders. But I also get some hidden/ignored folders that are not displayed in usual Outlook clients. I would like to ignore such folders as well.</p>
  
  <p>I tried to forge a request using SingleExtendedProperty and <a href="https://msdn.microsoft.com/en-us/library/ee200509(v=exchg.80).aspx" rel="nofollow">PigTagAttributeHidden</a></p>
  
  <blockquote>
    <p><a href="https://outlook.office365.com/api/beta/me/MailFolders" rel="nofollow">https://outlook.office365.com/api/beta/me/MailFolders</a>?$select=Id,DisplayName,ParentFolderId,ChildFolderCount,UnreadItemCount,TotalItemCount,SingleValueExtendedProperties&amp;$expand=SingleValueExtendedProperties($filter=(PropertyId eq 'Boolean 0x10F4'))</p>
  </blockquote>
  
  <p>In the results this property is always marked as false even for these "ignored" folders.</p>
  
  <p>Is there another way or fix to achieve this?</p>