This issue occurs in a Microsoft Exchange Server 2013 environment that has the UM Language Pack installed. A cumulative update installation removes the UM language pack before it continues the server upgrade. Additionally, if the log level for the
, Exchange server 2013 cannot upgrade, and the following error message is displayed in the ExchangeSetup.log file:
Setup will run the task 'remove-umlanguagepack'
Setup launched task 'remove-umlanguagepack -DomainController 'dc1.contoso.com' <…>'
[ERROR] Object reference not set to an instance of an object.
[WARNING] An unexpected error has occurred and a Watson dump is being generated: Object reference not set to an instance of an object.