Consider the following scenario:
You're on a Microsoft Lync Server 2013 RTM (5.0.8308.0) server that's running a non-English version.
You install the May 2015 Cumulative Update 5.0.8308.887 on the server.
You run the Bootstrapper.exe executable file.
In this scenario, Bootstrapper.exe can't be started. Additionally, you receive the following error message:
Error: The given key was not present in the dictionary.
└ Type: KeyNotFoundException
└ ▼ Stack Trace
└ at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at Microsoft.Rtc.Internal.Tools.Bootstrapper.BootstrapperTask.RemoveUnusedFeatures(Boolean scorch)
at Microsoft.Rtc.Management.Internal.Utilities.LogWriter.InvokeAndLog[T](Action`1 action, T arg)
This issue occurs because a change in the Microsoft.Rtc.Management.Deployment.dll file in the English version of the file hasn't been made available to the non-English version of the file.
To fix this issue, install the April 2016 cumulative update 5.0.8308.956 for the Lync Server 2013, Core Components.