I apologize for the delay responding back to you. Your code appears just fine. I was able to place it into a test project and run it (after pointing it to a different Silverlight application). Your symptom sounds like an IE add-on conflict. There is no special add-on for WebAii test scripts. We are able to find the open IE browser and automatically connect to it and begin controlling it without any add-on's. This KB article often helps with the problem you are describing (the IE window opens but then the framework throws a time-out exception connecting to the browser). Please pay particular attention to the section near the bottom about "Temporarily disable all Internet Explorer add-ons".
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