Outlook.MailItem.Open() function in my application is not getting called and application is stuck while opening mail item
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I have handled the Outllook.MailItem.Open event in a function like "myMailItem_Open()" in VB.NET like this:


Public Class MyHandler
    Protected WithEvents myMailItem As Outlook.MailItem = Nothing


    Private Sub myMailItem_Open(ByRef Cancel As Boolean) Handles myMailItem .Open
    // blah blah
    End Sub

End Class


When I click a certain "Tracking" button (Tracking button is got when we send a mail having voting option). Something is getting corrupted. 
And the next time I am trying to open a mail item, my function "myMailItem_Open()" is not getting called.
What could be the reason of this?? It is getting called in all other scenarios except when "Tracking" button is pressed. 
My app is not handling this "Tracking button" in any way.
