Complete the async operation started by BeginremoveTarget.
Assembly: Microsoft.Rtc.Collaboration (in Microsoft.Rtc.Collaboration.dll)
[T:System.ArgumentNullException]: Thrown when the parameter was null. The IAsyncResult is a required parameter.
[T:System.ArgumentException]: Thrown when the IAsyncResult object was created by a Begin method for a different operation.
[T:System.InvalidOperationException]: Thrown when the end was called multiple times.