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When you start the IISLog scenario by using the Start-CsClsLogging cmdlet in Microsoft Skype for Business Server 2015, the CLS log service crashes, and the following event is logged. This issue also occurs when you start CMDletDebug.

  • Log Name:      Lync Server

  • Source:        LS Centralized Logging Agent

  • Date:          DateTime

  • Event ID:      33040

  • Task Category: (1007)

  • Level:         Error

  • Keywords:      Classic

  • User:          N/A

  • Computer: ComputerName

  • Description:

  • Centralized Logging Service Agent Error starting background thread to process traces.

  • Log Type - IISLogManager, Error - Object reference not set to an instance of an object.

  • Cause: Internal error

  • Resolution:

  • Examine error details to determine resolution.

  • Event Xml:

  • <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">

  • <System>

  • <Provider Name="LS Centralized Logging Agent" />

  • <EventID Qualifiers="50159">33040</EventID>

  • <Level>2</Level>

  • <Task>1007</Task>

  • <Keywords>0x80000000000000</Keywords>

  • <TimeCreated SystemTime=" DateTime" />

  • <EventRecordID>39492</EventRecordID>

  • <Channel>Lync Server</Channel>

  • <Computer>ComputerName</Computer>

  • <Security />

  • </System>

  • <EventData>

  • <Data>IISLogManager</Data>

  • <Data>Object reference not set to an instance of an object.</Data>

  • </EventData>

  • </Event>


To fix this issue, install the latest cumulative update for Skype for Business Server 2015.

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