Closed Unassigned: Recently we got AccessViolationException [12019]

Hi! Recently we've got the following exception. It happened one time and we cannot reproduce it.

System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.AccessViolationException: Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
at Microsoft.Win32.TaskScheduler.V2Interop.IRegisteredTask.get_Definition()
at Microsoft.Win32.TaskScheduler.Task.GetV2Definition(TaskService svc, IRegisteredTask iTask, Boolean throwError)
at Microsoft.Win32.TaskScheduler.Task.get_Definition()


We run our WPF application on Win7, .Net 3.5.