Exchange 2013 running on virtual server Hyper V
Hyper V server windows Server 2012 R2
Exchange 2013 setup in hybrid mode with Office 365
Mail stops flowing for no reason, I opened a ticket with Office 365 Support, and after several checks and adjustments no solution.
Last suggestion from Office 365 Support team was to check Time sync Issues/configuration on Hyper V Server.
Can this cause mail to stop flowing?
Solution to get mail flowing again has been to shut down Exchange down
Reboot Hyper V server and restart Exchange
Average uptime for exchange is 24 to 36 hours.