Message in Dutch (Nederlands)
Het IAsyncResult-object is niet afkomstig van de corresponderende async-methode voor dit type, of de End-methode is meermaals aangeroepen met hetzelfde IAsyncResult.
Unlocalized message
Either the IAsyncResult object did not come from the corresponding async method on this type, or the End method was called multiple times with the same IAsyncResult.
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