Checked ListView Count - NullReferenceException

[Zeljko]

Win XP, VS 2008, .NET 2.0

When I use Count property to count checked items in ListView (set to detail view with check boxes), sometimes i get NullReferenceException on count part. Sometimes I get it but sometimes I don't get it... It's very randomly and I can not reproduce it always?!? It just happens sometimes
Can somebody tell me why or point me a lil bit?

CODE:
Private Sub LstVew1_ItemChecked(ByVal sender As System.Object, ByVal e As System.Windows.Forms.ItemCheckedEventArgs) _
Handles LstVew1.ItemChecked
   If LstVew1.CheckedItems.Count > 1 Then
     lbl1.Text = "Selected items: " & LstVew1.CheckedItems.Count
   Else
     lbl1.Text = "U have 1 or 0 selected item(s)"
   End If
End Sub
 
CODE EXCEPTION:
System.NullReferenceException: Object reference not set to an instance of an object.
   at System.Windows.Forms.ListView.CheckedIndexCollection.get_Count()
   at System.Windows.Forms.ListView.CheckedListViewItemCollection.get_Count()
   at ...

Thanks in advance

[Negative0]

Try and figure out what is null. Is it the listview or is it the checked collection?

Do you ever call .Dispose on the listview?

[Zeljko]

The problem is that I really don't know for sure on which part is error exactly while this never happened in debuger (in vs environment). This happens on rare occasions (like 1 per week) and in exe file on some machine... Never on my machine

- I don't call dispose for list view. Do u think that not disposing it cause souch problems? I can not dispose it while I use it when is form opened. ListView is filled with data and when using it, some data gets checked by user some gets unchecked, so I need it and i cant dispose it.

Yesterday evening I heard some guys talking about that they get exactly the same error on listview.checked.count part and they suspect .net 2 framework bug. Hmmm. If that is the case can i count it in another way... more safer way?

[Zeljko]

New updates on this bug.

I isolated this bug to users that have installed on their computers maximum original .NET framework 2 with no service pack and no .net 3 and no .net 3.5. Strange that affects only users with NET 1/1.1 and NET 2. Other users seems to be fine...

If that is the case, I am now interested in finding another way to count checked items in listview? Is there?