The inner exception stack traces are not getting displayed in Unity errors, as a result only the last stack trace is being displayed - sending newbies (like me) down a rabbit trail.  I was refactoring an application which relied on a factory and numerous concrete classes which had been retrofitted for Unity.  I had intrepeted the error to be a configuration error, later I learned (after much debugging) that it was actually a null object references dangling during the conversion.  The following is the error message I received:

Resolution of the dependency failed, type = "Form1", name = "". Exception message is: The current build operation (build key Build Key[TestHarness.Form1, null]) failed: The value for the property "Presenter" could not be resolved. (Strategy type Microsoft.Practices.ObjectBuilder2.BuildPlanStrategy, index 2)

After updating the ResolutionFailedException.cs CreateMessage() as follows:

        private static string CreateMessage(Type typeRequested, string nameRequested, Exception innerException)
        {
            return string.Format(
                CultureInfo.CurrentCulture,
                Resources.ResolutionFailed,
                typeRequested.Name,
                nameRequested,
                GetInnerExceptionMessage(innerException));
        }

        /// <summary>
        /// Recursive routine to collect all inner exception errors
        /// </summary>
        /// <param name="ex"></param>
        /// <returns></returns>
        private static string GetInnerExceptionMessage(Exception ex)
        {
            StringBuilder errorMessage = new StringBuilder(ex.InnerException.Message);
            errorMessage.Append(ex.InnerException.StackTrace);
            errorMessage.Append("\r\n");

            if (ex.InnerException.InnerException != null)
                errorMessage.Append(GetInnerExceptionMessage(ex.InnerException.InnerException));

            return errorMessage.ToString();
        }

I received the following error message which allows me to isolate issues more quickly: