[ms office - 2016] Outlook 2016 Sync Issues with e-mails?

[jawebber]

Hi all,

 

A strange one that I hope someone else has had on their network and knows how to fix! Teachers log on to a PC in their classroom and sort a few e-mails into folders, delete or archive them. They log off, and/or log on to another PC, and sometimes those emails are back in the original place.

 

I imagine the local computer hasn't synced up to the O365 server to update this, but on the face of it, it looks fine - the toolbar says "Connected to: Microsoft Exchange" although as the PST is downloaded on every login it may also be "Updating Sent Items" or populating other folder at the same time as we're using Cached Exchange Mode and downloading all mail items online... with the OST file held in the C:\Users\..\AppData folder rather than on the shared drive.

 

Could any of this be the issue? Thanks on any advice!