out of office not working from outlook client

I have an Exchange 2016 server which is updated to the latest CU and security updates.   out of office from the outlook client has quit working and I have been unable to get it working.  It works fine from OWA.  There are some WAS 5011 warnings in the event log.  A process serving application pool 'MSExchangePowerShellFrontEndAppPool' suffered a fatal communication error with the Windows Process Activation Service.  any ideas would be greatly appreciated.