I use regular Office/Outlook 2016 (not Office 365). In my Outlook I use an OST account that is linked to my providers IMAP. In the same Outlook profile/account I added a PST data file to use as my archive. So I move mails from the OST to my PST when I'm done with them.
Now all of a sudden, Outlook creates private folders that are present in my PST data file inside the OST data file. The folders themselves are empty. When I check my webmail on the mail provider none of these folders are there.
So I assume these are not really IMAP linked folders but some kind of "ghost" copy between the PST and OST file. When I delete these emtpy folders in my OST they'll eventually reappear like out of nowhere.
Does anyone know what might be causing this and how to make Outlook stop creating these folder copies in my OST data file?