Issue using silverlight 4 as development environment

i am running visual studio 2010, and as soon I choose Silverlight 4 as build environment, it prompts me to download developer tools for silverlight 4 (http://go.microsoft.com/fwlink/?LinkId=168436)

I have downloaded it multiple times and even restarted machine.

Does anyone k开发者_如何学Gonow what could be the potential issue?

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Turns out that if you have an old build of windows phone developer tools http://developer.windowsphone.com than it does interfere with Silverlight 4 dev bits.

Apparently, new http://developer.windowsphone.com build doesnt have that issue