Не удается получить доступ к узлам дерева с помощью TestStack.White

Я пытался автоматизировать представление календаря Ms Outlook с помощью TestStack.White, но не могу обрабатывать деревья и элементы дерева.

В представлении календаря Outlook есть дерево Папки календаря со следующей структурой:

SearchCriteria searchCriteria = SearchCriteria.ByText("Calendar Folders").AndControlType(ControlType.Tree).AndIndex(0);
Tree calendarTree = (Tree)WhiteWindows.mainWindow.Get(searchCriteria);

calendarTree.Click(); // this action is performed correctly - clicks on the tree

Console.WriteLine("No. of nodes: " + calendarTree.Nodes.Count); // this line throws an exception

что-нибудь:

Result StackTrace:  
at TestStack.White.Mappings.ControlDictionary.GetTestControlType(String className, String name, ControlType controlType, String frameWorkId, Boolean isNativeControl) in c:\TeamCity\buildAgent\work\89a20b30302799e\src\TestStack.White\Mappings\ControlDictionary.cs:line 157
   at TestStack.White.Mappings.ControlDictionary.GetTestControlType(AutomationElement automationElement) in c:\TeamCity\buildAgent\work\89a20b30302799e\src\TestStack.White\Mappings\ControlDictionary.cs:line 218
   at TestStack.White.Factory.DictionaryMappedItemFactory.Create(AutomationElement automationElement, ActionListener actionListener) in c:\TeamCity\buildAgent\work\89a20b30302799e\src\TestStack.White\Factory\DictionaryMappedItemFactory.cs:line 13
   at TestStack.White.UIItemList`1..ctor(List`1 collection, UIItemFactory factory, ActionListener actionListener) in c:\TeamCity\buildAgent\work\89a20b30302799e\src\TestStack.White\UIItemList.cs:line 26
   at TestStack.White.UIItems.TreeItems.Tree.get_Nodes() in c:\TeamCity\buildAgent\work\89a20b30302799e\src\TestStack.White\UIItems\TreeItems\Tree.cs:line 54
   at TestStack.White.Bricks.DelegateInvoker.ActionInvokerWrapper`1.Call(Object[] args) in c:\TeamCity\buildAgent\work\89a20b30302799e\src\TestStack.White\Bricks\DelegateInvoker.cs:line 198
   at TestStack.White.Bricks.DynamicProxyInterceptors.Process(IInvocation invocation, CoreInterceptContext interceptedContext) in c:\TeamCity\buildAgent\work\89a20b30302799e\src\TestStack.White\Bricks\DynamicProxyInterceptors.cs:line 21
   at TestStack.White.Interceptors.CoreInterceptor.Intercept(IInvocation invocation) in c:\TeamCity\buildAgent\work\89a20b30302799e\src\TestStack.White\Interceptors\CoreInterceptor.cs:line 31
   at Castle.DynamicProxy.AbstractInvocation.Proceed()
   at Castle.Proxies.TreeProxy.get_Nodes()
   at UI.Tests.StepDefinitions.TempSteps.WhenCalendarIsSelectedOnPage(String p0, String p1) in StepDefinitions\TempSteps.cs:line 183
   at lambda_method(Closure , IContextManager , String , String )
   at TechTalk.SpecFlow.Bindings.BindingInvoker.InvokeBinding(IBinding binding, IContextManager contextManager, Object[] arguments, ITestTracer testTracer, TimeSpan& duration)
   at TechTalk.SpecFlow.Infrastructure.TestExecutionEngine.ExecuteStepMatch(BindingMatch match, Object[] arguments)
   at TechTalk.SpecFlow.Infrastructure.TestExecutionEngine.ExecuteStep(StepInstance stepInstance)
   at TechTalk.SpecFlow.Infrastructure.TestExecutionEngine.OnAfterLastStep()
   at TechTalk.SpecFlow.TestRunner.CollectScenarioErrors()
   at UI.Tests.Features.PlaygroundFeature.ScenarioCleanup() in UI.Tests\Features\Playground.feature.cs:line 0
   at UI.Tests.Features.PlaygroundFeature.SelectNewCalendar() in UITests\Features\Playground.feature:line 11
Result Message: 
Test method UI.Tests.Features.PlaygroundFeature.SelectNewCalendar threw exception: 
TestStack.White.Mappings.ControlDictionaryException: Multiple TestControls found for ControlType=tree view item and FrameworkId: - TestStack.White.UIItems.TreeItems.Win32TreeNode, TestStack.White.UIItems.TreeItems.WPFTreeNode, TestStack.White.UIItems.TreeItems.Win32TreeNode

Для следующего фрагмента кода возникло такое же исключение:

foreach(TreeNode node in calendarTree.Nodes) // Exception thrown here
{
    //perform action on nodes
}

У кого-нибудь есть обходной путь для этого?