I have more than a dozen of monitored email address that create cases.
it appears that the O365 performance/ responsiveness is making my process unreliable. often it will fetch the mailbox of only 50% of the accounts and the process is always starting from the same account… so it may take 10 hours before an mailbox is fetched…
Does anyone else use O365 with many CRM inbound emails?
if so what is your satisfaction with them do you have the same issue that I have?
Serge
There are a lot of performance problem with O365.
To improve the speed we had used imapproxy (http://www.imapproxy.org/) that “is a caching IMAP proxy server intended for use with webmail clients that cannot maintain persistent connections” because one problem is the long time to create a connection. With imapproxy we had good benefit in performance.
We had also try to create a cache mail server but is an “hard work” 
Thank you Roberto for your idea, I will look this up…
your “solution/setup” make sense…