While recording a user profile from a data driven web test, intermittently the ArtOfTest.Runner may crash with System.InvalidOperationException. Attached is the test and data file I used that created this problem. It took two runs to reproduce it. In the event log is this stack trace:

Application: ArtOfTest.Runner.exe
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.InvalidOperationException
Stack:
   at System.ThrowHelper.ThrowInvalidOperationException(System.ExceptionResource)
   at System.Collections.Generic.List`1+Enumerator[[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].MoveNextRare()
   at System.Collections.Generic.List`1+Enumerator[[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].MoveNext()
   at System.Linq.Enumerable.FirstOrDefault[[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]](System.Collections.Generic.IEnumerable`1<System.__Canon>, System.Func`2<System.__Canon,Boolean>)
   at ArtOfTest.WebAii.Design.TrafficRecording.HttpTrafficRecorder._proxy_ResponseHandler(System.Object, ArtOfTest.WebAii.Messaging.Http.HttpResponseEventArgs)
   at ArtOfTest.WebAii.Messaging.Http.HttpProxyManager.EventListenerThread(System.Object)
   at System.Threading.ThreadHelper.ThreadStart_Context(System.Object)
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
   at System.Threading.ThreadHelper.ThreadStart(System.Object)