In Windows 10 Mail app, my Outlook account is set to sync "as items arrive". My Gmail account is set to "based on my usage", but it shows that it is currently using "as items arrive". I want to set my IMAP account to "as items arrive", but that option is not available. It is my understanding that only two accounts can use "as items arrive". How do I make the IMAP account sync "as items arrive"? Also, the IMAP account does not show up in the Calendar app, but the other two accounts are there.