We are seeing some sort of malfunction on OWA or client front end on Exchange 2016:

Log Name: Application
Source: MSExchange Common
Date: 23/11/2018 07:46:34
Event ID: 4999
Task Category: General
Level: Error
Keywords: Classic
User: N/A
Computer: %computername%.domain.suffix
Description:
Watson report about to be sent for process id: 31952, with parameters: E12IIS, c-RTL-AMD64, 15.01.0466.037, w3wp#MSExchangeOWAAppPool, M.E.C.Owa2.Server, M.E.C.O.S.C.OwaMapiNotificationManager.SubscribeToSuiteNotification, System.NotSupportedException, 2c3e, 15.01.0466.037.
ErrorReportingEnabled: True

Event Xml:



4999
2
1
0x80000000000000

9626852
Application
%computername%.domain.suffix



31952
E12IIS
c-RTL-AMD64
15.01.0466.037
w3wp#MSExchangeOWAAppPool
M.E.C.Owa2.Server
M.E.C.O.S.C.OwaMapiNotificationManager.SubscribeToSuiteNotification
System.NotSupportedException
2c3e
15.01.0466.037
True
False
w3wp#MSExchangeOWAAppPool

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