Service Reference client bug?

Hi i have a WPF application that uses a service reference to a web service...

Now i have a GUI component that tracks the progress of this...

But i seem to have some sort of bug here, it only occurs on some machines and not often.. I start a call with MethodNameAsync and display the progress bar until the matching Completed event occurs.

some times i call 3 different async methods in a row but only the two of them get their Completed event raised so the GUI will be locked and the application has to be restarted.

After being totally frustrated a few weeks i found the event AppDomain.CurrentDomain.FirstChanceException, so i hooked up to it and started logging all FirstChanceExceptions..

Before the second event is raised a System.Net.Sockets.SocketException "An invalid argument was supplied" is thrown and after that a System.ObjectDisposedException "Cannot access a disposed object." is thrown both are first chance exceptions..

i guess my wcf client forgets about the third method call when this happens but my loading indicator does not..

So is this a known bug or am i missing some thing?

Edit code as requested:

mCheckInService = New CheckInServiceClient()
AddHandler mCheckInService.GetPersonActivitiesCompleted, AddressOf CheckInService_GetPersonActivitiesCompleted
AddHandler mCheckInService.GetPersonArticlesCompleted, AddressOf CheckInService_GetPersonArticlesCompleted
AddHandler mCheckInService.GetPersonImageCompleted, AddressOf CheckInService_GetPersonImageCompleted


Dim workItem As WorkItem = Context.WorkDisplayService.AddWorkItem(Me, Resources.Label.DownloadingPersomImage)
mCheckInService.GetPersonImageAsync(Context.Session, person, workItem)

workItem = Context.WorkDisplayService.AddWorkItem(Me, "Hämtar aktiviteter")
mCheckInService.GetPersonActivitiesAsync(Context.Session, Person, workItem)

workItem = Context.WorkDisplayService.AddWorkItem(Me, Resources.Label.DownloadingPersonArticles)
mCheckInService.GetPersonArticlesAsync(Context.Session, person, workItem)


Private Sub CheckInService_GetPersonActivitiesCompleted(ByVal sender As Object, ByVal e As GetPersonActivitiesCompletedEventArgs)
    Dim workItem As WorkItem = CType(e.UserState, WorkItem)
    If (Context.WorkDisplayService.FinishWorkItem(Me, workItem)) Then

Private Sub CheckInService_GetPersonArticlesCompleted(ByVal sender As Object, ByVal e As G开发者_运维百科etPersonArticlesCompletedEventArgs)
    Logger.Trace("CheckInService_GetPersonArticlesCompleted()")
    Dim workItem As WorkItem = CType(e.UserState, WorkItem)
    If (Context.WorkDisplayService.FinishWorkItem(Me, workItem)) Then

Private Sub CheckInService_GetPersonImageCompleted(ByVal sender As Object, ByVal e As GetPersonImageCompletedEventArgs)
    Logger.Trace("CheckInService_GetPersonImageCompleted()")
    Dim workItem As WorkItem = CType(e.UserState, WorkItem)
    If (Context.WorkDisplayService.FinishWorkItem(Me, workItem)) Then

Its GetPersonActivitiesAsync that never gets completed..

Edit:

Fix this temporary by not using async methods and instead using a thread that will call them one by one.. now this is not a elegant solution, i should be able to use the async methods...

The clue here is "Cannot access a disposed object".

What sometimes happens with callback code is that the code that should be listening for the callback has been disposed, so when the callback comes back, nobody is listening.