Summary
This update fixes the issue that the Microsoft Skype for Business Server 2015 UCMA-based services, such as Skype for Business Server Audio/Video Conferencing Unit (AVMCU), Skype for Business Server Application Sharing (ASMCU), Skype for Business Server Conferencing Auto Attendant (CAA), Mediation Server and so on, may crash on service startup when running on Windows Server 2016. The crash has a call-stack that's similar to the following:
Second chance exception on worker thread. Thread: 21, Exception: Exception: System.ArgumentOutOfRangeException > Message: The value 3905470566 is out of the expected range 0..2147483647. Parameter name: value > ParamName: value > TargetSite: Void ThrowIfIntOutOfRange(Int64, Int64, Int64, System.String) > StackTrace: at Microsoft.Rtc.Signaling.ArgumentVerifier.ThrowIfIntOutOfRange(Int64 number, Int64 minValue, Int64 maxValue, String paramName) at Microsoft.Rtc.Signaling.SdpBandwidth.set_Value(Int64 value) at Microsoft.Rtc.Internal.Collaboration.Media.SdpMediaSession`2.GenerateSdp(SdpDialogNegotiationContext dialogContext, GenerateSdpReason reason) at Microsoft.Rtc.Internal.Collaboration.Media.SdpMediaSession`2.GenerateAnswer(Object dialogId) at Microsoft.Rtc.Collaboration.AudioVideo.MediaSessionAgent.ProcessGenerateAnswerWorkitem(GenerateAnswerWorkitemAsyncResult workitem) at Microsoft.Rtc.Signaling.WorkitemQueue.ProcessItems() at Microsoft.Rtc.Signaling.QueueWorkItemState.ExecuteWrappedMethod(WaitCallback method, Object state) > Source: Microsoft.Rtc.Collaboration > HResult: -2146233086
Resolution
To fix this issue, install the January 2019 cumulative update 6.0.9319.537 for Skype for Business Server 2015 and Unified Communications Managed API 5.0 Runtime.
