If you installed Expression Blend2 August Preview you probably noticed the splash screen prompts you for a product key...even giving you a link to get this key.   Unfortunately there was a little confusion with the folks that built the splash screen as Blend 2 August Preview comes pre-keyed which is good through Oct 31.  Unfortunately the link the splash screen directs you to doesn't have a key as there are no keys for this build.

 

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