Can't help. sorry, but using Outlook on Windows H'eight, downloaded from an old Office 2007 disc. I know that there is an option to retain /or delete items from the server. Maybe you need to play around with all ( if any ? ) options available ?
I couldn't get my old WAB ( Windows Address Book ) now called Contacts, to move over to Outlook from my previous Outlook Express, either, and try as I might I'm unable to get Groups added to an outgoing e-mail. I've started all over again creating new groups, but I just get the message - unable - or words to that effect.
Life Was Easier before Outlook, Windows H'eight and now it appears Windows 10, which I'm steering well clear of as long as possible, having installed my old Office 2007, and Word 97 I'm reasonably happy, they do all I want.
Why the fcuk do THEY have to change everything, if it ain't broke, don't fix it.
Best of luck, I'm sure there are better brains than mine out there who will come to your aid.