Hey Patty-psv
Here is what I did and my notes were ok afterwards. Before I deleted my account, I moved all messages in ARCHIVE TO INBOX. I have an iPhone 6S with APPLE MAIL, went to SETTINGS, then MAIL, in Mail I went to ACCOUNTS chose what Account I wanted, DELETED the Account I needed to delete..ATERWARDS, I went back to Accounts in Mail and clicked on ADD ACCOUNT, chose OUTLOOK.COM then SIGNED IN by entering the same info needed for the Account that I had just deleted..after I had signed in, the Outlook page showed up with the name of the Account and Tabs for Mail, Contacts, Calendars, Reminders, and Notes..then I chose which ones I wanted to be reactivated, showing in green and clicked at the Bottom where it says MAIL DAYS TO SYNC and CLICK on NO LIMIT This is what I did and everything works..Sometimes in Archive messages say can’t open because not downloaded from server but most are ok. I hope this helps someone.
By the way you can delete the account and re add it as many times as you feel satisfied that everything is ok..I have done this with 2 iPhones, one IPad..All is ok with Outlook and Windows 10 on my PC no need to change anything there.