Asp.net mvc3 runtime errors

I have updated to asp.net mvc3 from Microsoft site, but running it in vs2010 have errors:

Could not load file or assembly 'Microsoft.Web.Infrastructure, Version=1.0.0.0, Culture=neutral, PublicKeyT开发者_运维问答oken=31bf3856ad364e35' or one of its dependencies. The module was expected to contain an assembly manifest.

Then I added Microsoft.Web.Infrastructure in solution referece, still have problem. Using gacutil /i Microsoft.Web.Infrastructure cannot work. So how to solve this problem?

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May you try to update your environment using Microsoft Web Platform Installer. To run asp.net mvc3, you need also to install SP1 of VS10, but you can install all you need from the Web Platform Installer.

http://www.microsoft.com/web/downloads/platform.aspx