Classic Outlook folder and favorites issues

I have a single user who is experiencing the most frustrating issues with outlook classic.

1. Pinned favorites
   My co-worker has 3 accounts in her Outlook and pins the inboxes of those accounts to her favorites. Every time she reboots her PC, some or all of the pined inboxes are removed from her favorites. She can add them again, but they do not stay.
   
   
2. My co-worker has organized all of her saved email into many folders within the 3 email accounts. We setup outlook to cached mode and to download the most recent year. she used to get the link in folders to see items older than a year. Sometimes all items even older than a year will display, sometimes no messages show. She has learned that when messages are not loading into folders, she can reboot her PC to get the items to load. 

I have deleted and reinstalled office 365 apps, created a new outlook profile, I even had her login to the 3 accounts rather than relying on permissions being granted via the server. I am unsure what else to do. Can someone assist me?

We do work with an outside tech firm and their solution was to use the new outlook but that came with a list of things that would not work. I'd simply like to get classic outlook to function as expected.