If you do not do this, your Inbox could remain empty and other folders might not sync or show up at all and move, copy and delete actions could result in permission errors.
Symptoms: Outlook 2016 is only pulling emails from subfolders. Solution: Check if the path to your Inbox is set in your Outlook 2016 settings. Tab: Advanced Option: Root folder path Setting this to “Inbox” will do the trick. To set the root folder path for your IMAP account: File- Account Settings… Before emptying the cache, you may want to ensure that your Outlook information is backed up.If your Auto/Send Receive stops working for some reason it can be pretty frustrating because you have to remember to manually do a Send/Receive (F9). “ Actually, the November update for Outlook 2013 (KB2837618) fixes a whole lot of IMAP issues and is highly recommended.
Amongst others, the update makes sure that IMAP accounts will not repeatedly completely resynch folders, will not create duplicates of default folders, will more reliably map the special server folders and make it less likely that folders will get marked as “This computer only”.However, it is now also more important than ever to correctly set the Root Folder Path for your mailbox when your IMAP server requires it.Unfortunately, Outlook doesn’t detect this automatically but you need to set it manually.Ost-file isn’t recoverable: possible loss of Calendar and Contacts Another important thing to keep in mind is that the ost-file of an IMAP account isn’t recoverable without using (expensive) 3rd party tools; You can’t reuse the ost-file when you recreate the account or move it to another computer!This means that all the folders which have “This computer only” behind them will be lost if you do not export them.When it comes to support with security updates and confirmed software bugs, no support charges will apply but you might need to supply credit card information to open the support case. Language issues If you are working with an IMAP server which is using names for special folders in a language other than your language of Outlook, these special folder might not be recognized in Outlook and local “This computer only” folders might be created.