Until recently. there was never a problem where email in ALL folders would not download when Sending/Receiving mail in Outlook 2016 was manually or automatically executed.
As couple of days ago I was helping a client who was missing email. Turns out the email was flagged a spam. This is not the problem though. We have ingrained the need to check the spam folder before contacting us in our clients.
The issue is: Outlook is no longer retrieving email for ALL folders simultaneously. Users are now having to open individual folders then click update for get mail for any folder that is not the main Inbox.
This is happening across multiple domains and accounts that we manage. This effecting every folder excluding the main Inbox though it is effecting ALL sub-folders in the inbox.
Considering the fact that we have the access... we have checked this against GSuite Enterprise, Office 365 Enterprise, and NameCheap's hosted email services. This is ONLY occurring with ZohoMail.