Visual Studio 2010 RC is built against the ASP.NET MVC 2 RC version but you can easily install ASP.NET MVC 2 RTM on the Visual Studio 2010 RC. For installing ASP.NET MVC 2 RTM, do the following steps

1. Uninstall "ASP.NET MVC 2 ". 
2. Uninstall "Microsoft ASP.NET MVC 2 – Visual Studio 2008 Tools" If you have previously installed  ASP.NET MVC 2 template for VS 2008.
3. Install the new ASP.NET MVC 2 RTM version for Visual Studio 2008 SP1.

The above steps will enable you to use ASP.NET MVC 2 RTM version on the Visual Studio 2010 RC.

Note : Don't uninstall Microsoft ASP.NET MVC 2 – Visual Studio 2010 Tools

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