We often tell users to right click on the "root folder" but where exactly is that?
Outlook's root folder is the top folder in your data file, where Outlook Today is.
Right click on it and choose Properties (Data File Properties in Outlook 2010).
From here you can check the size of the data file andeach folder within the data file; change or disable the folder home page, set permissions (Exchange mailboxes only); abd compact the data file.
I recently installed O365 E5 desktop Office including Outlook client. I have 3 accounts. 2 Exchange and a Gmail (setup as IMAP) account. I was having sync problems with Gmail and while I was exploring I changed the root folder in that account to Inbox. Immediately my personally-created folders disappeared. So too did the deleted folder. And, now, I cannot even delete any messages from inbox now either. Displays "The operation cannot be performed because the object has been deleted". I check on gmail online (webmail) and it's very much still in the inbox. I've tried the subscribed route and nothing. What have I "broken"?