Microsoft 365 IMAP implementation doesn't correlate with Outlook 2019 desktop application

Question

I'm using IMAP to connect to one of my Microsoft 365 accounts to avoid joining all Office applications to that account.

Doing so I couldn't fail to recognize a number of flaws in Microsoft 365 and Outlook 2019 when connected via IMAP:

1. Folders don't match
   1. Outlook Online displays the same folders twice, once in German and once in English.
   2. Outlook 2019 doesn't display well-known folders' content. In the example image below, the Sent Items folder is empty in Outlook 2019 while it is not in Outlook Online.
   3. Outlook 2019 doesn't display custom folders at all.
2. After I sent an e-mail, it apears twice in Sent Items in Outlook 2019.

I'm not sure if this is rather a Microsoft 365 flaw or an Outlook 2019 desktop application flaw, so I'll start posting my observations here.

Answer 1

Hi BetterToday

Greetings

Thank you for posting in Microsoft Community.

1. Outlook 2019 doesn't display well-known folders' content. In the example image below, the Sent Items folder is empty in Outlook 2019 while it is not in Outlook Online.

Please try to disable the Show only subscribed folder option from your Outlook 2019 desktop client.

Click on the folder tab then click on IMAP folders

Then an page will pop up showing the IMAP folders. You should see an option that says when displaying hierarchy in Outlook, show only the subscribed folders. If that option is ticked please untick it, then restart Outlook to see if your custom folders still don't show.

You may also try to change the Root folder Path by doing the following;

#Navigate to File >Info> Account settings> Account setting

Then select your IMAP account then select Change >More Settings > Advanced, on the advanced page please try to look for Root folder path and enter INBOX with capital letters.

Click ok >Next > Finish

2.Outlook 2019 doesn't display custom folders at all.

You may try to choose which Outlook folders are not appearing in the folder pane by doing the following:

In the navigation pane right click on the IMAP account and select IMAP folders

 # Then click query to display a list of all the IMAP folders on the mail server.

Then select the IMAP folders that don't appear on the navigation pane and select subscribe, and repeat this for any other folder that you want to appear on the navigation pane. Then click ok

Then right click, the IMAP account and select the Update folder list to apply the changes.

Outlook Online displays the same folders twice, once in German and once in English.

Regarding this query you may refer to the article How to remove duplicate folders in Outlook when connected to an Exchange Server mailbox (microsoft.com)

After I sent an e-mail, it appears twice in Sent Items in Outlook 2019.

You may refer to the trouble shooting steps listed in IMAP Sent Messages are duplicated and unread in Sent Items folder (microsoft.com)

Please feel free to let me know how it goes.

Kind Regards,

Momo

Answer 2

Hi Momo,

thank you for your reply.

Now, this is what I did:

1. I launched a VM having Office 2019 installed. (Outlook never ran on that machine.)
2. I launced a new copy of Outlook 2019 and created an Outlook IMAP type of account for the above mentioned Microsoft 365 account.
3. After having created that account, only five folders appeared in that Outlook 2019 instance:
   1. Posteingang [= Inbox]
   2. Entwürfe [= Drafts]
   3. Postausgang [= Outbox]
   4. RSS-Feeds (Nur dieser Computer)
   5. Suchordner [= Search folder]
      (NB: "Gesendete Objekte" (= Sent Items) did not appear)
4. I right-clicked the IMAP account and selected the "IMAP Folders ..." menu item in the Outlook 2019 copy.
5. Surprisingly, the list of folders listed as being subscribed contained (among the ones mentioned above):
   1. Deleted Items
   2. Drafts
   3. Junk Email
   4. Sent Items
6. I removed subscription from those folders.
7. In the VM's Outlook 2019 copy, the list of folders wasn't updated. Still only the above mentioned four folders (step #3) were displayed.
   So, I switched to my local machine and launched Outlook 2021 there.
8. In Outlook 2021, I deleted the English folders – this time successfully !!

So, apparently, the key to removing the English folders was to remove their subscription.

I'm not sure if I could have seen the full list of subscriptions in Outlook 2021. When I now open the "IMAP Folders ..." menu item in any of the Outlook instances, the English folder names don't appear.

Your help was very helpful to me!

Above, I listed my final steps in solving this issue thoroughly, so anyone else facing a similar issue may find this thread helpful.

Answer 3

Hi Betterday

Apologies for the late response.

Please let me know if the folders you want to delete from Outlook on the Web app, are not the same folders you subscribed to on Outlook client?

According to the article Can't move or delete folder in Outlook online mode if the destination has a folder with the same name in Exchange Server 2019 and 2016 (microsoft.com) if you do happen to use any of the mentioned servers, then it could be that a folder with the same name already exists in the deleted items folder, please try to refer to the solution in the article. If this is not your scenario, please feel free to let me know.

Kind Regards,

Momo

Answer 4

How can I delete English IMAP folders (see above)?

Answer 5

Thank you, Momo, for your informative reply!

Yesterday, I migrated to Outlook 2021, so a few things changed.

Following are the results after migrating (and, still, one issue occurs):

1. After I sent an e-mail, it apears twice in Sent Items in Outlook 2019
   Your suggestion worked!
   IMAP Sent Messages are duplicated and unread in Sent Items folder
2. Outlook 2019 doesn't display custom folders at all
   Your solution worked!
3. Outlook Online displays the same folders twice, once in German and once in English
   I noticed that this issue was introduced when I switched my inbox language from German to English. Now I switched back to German again. Nonetheless, I cannot delete the English folders (see below)
   Folder names are incorrect or displayed in an incorrect language in Outlook

Could you also enlighten me on how to delete these? It looks like a server issue to me..?

Your help is very much appreciated!