MS Graph List Mailfolders not returning all the folders

Question

I'm using MS Graph to get all the folders in a mailbox using the following URL:

https://graph.microsoft.com/v1.0/users/{mailbox}/mailFolders

This returns 10 folders. I then use the URL returned in @odata.nextLink to call the API again, repeating this until there are no more. In total I get 39 folders returned.

But, when I look at the mailbox, it has far more than 39 folders. Why is MS Graph not returning them all - they are all under the same parent folder.

I've tried adding ?$top=100 at the end of the inital URL, but it still only returns 39.

Is this a bug in MS Graph ?

Answer 1

Hi, have you found the answer?

I am having a similar issue. I am not getting all the sub mailfolders of the parents unless the sub mailfolders were created by the application user that I used to access the inbox.
I have applied all required permission for the application user.

• Mail.ReadBasic.All
• Mail.Read
• Mail.ReadWrite

I used the following code:

var queryOptions = new List<QueryOption>()
{
new QueryOption("includeHiddenFolders", "true")
};

var TestOCFolders = await graphClient.Users[destination.Email].MailFolders[FolderId].ChildFolders.Request().GetAsync();

var OCFolders = await graphClient.Users[destination.Email].MailFolders[FolderId].ChildFolders.Request(queryOptions).Top(250).GetAsync();

Answer 2

I was having the same issue while using the same URL.

Not sure if this will be relevant to you - but I'm hoping it may be to someone else if not as this had me pulling my hair out.

The mailbox I was running this against had been imported into MS365 from Gmail. As such, all of the imported folders had their PR_CONTAINER_CLASS value set to IPF.Imap, once I changed these to IPF.Note using MFCMAPI and relaunched Outlook the API call was returning them.