IPF.Imap can not be listed by graph api /users/{user_id}/mailFolders/{folder_id}/childFolders

Question

As stated in the title, I am unable to list folders with FolderClass="IPF.Imap" using graph api /users/{user_id}/mailFolders/{folder_id}/childFolders.

However, the IPF.Imap folders are listable by graph api /users/{user_id}/mailFolders/{folder_id} (eg. given folder id) and also listable by ews api SyncFolderHierarchy.

Is this a limit by graph api?
Thank you in advance.

Answer 1

I don't think Graph shows IPF.Imap folders. Try to either remove the PR_CONTAINER_CLASS MAPI property or set its value to "IPF.Note". If it is a one-time deal, you can edit/delete that property in OutlookSpy (I am its author, select the folder in Outlook, click IMAPIFolder button on the OutlookSpy ribbon, select the PR_CONTAINER_CLASS property), otherwise you should be able to change that property programmatically using Outlook Object Model (MAPIFolder.PropertyAccessor.SetProperty) or Extended MAPI on the client side.