How do I select the right version of the CLR in VS2010?

At the time of creating the new project, i not able to session entry for previous version of .net framework in the drop drown box it should only .net Framework 4 and hyper link for more framework.Even those i have 开发者_StackOverflow.net 2.0 ,3.0 and 3.5.

Can anyone suggest me what can be done?

Thanks and Regards Sameer ahmed.s

VS2010 requires full (not just client profile) .NET 3.5 SP1 to be installed to support down version targeting. More details here: http://blogs.msdn.com/webdevtools/archive/2010/04/22/framework-net-3-5-sp1-required-for-targeting-lower-frameworks-2-0-3-0-and-3-5-multi-targeting-using-visual-studio-2010.aspx

Once a project is created you can change the targeted version in the project properties.

Some project types won't allow you to select older versions - what is your project type? Can you select the framework version on something like a Console Application?

Also, do you have the SDK versions of 2.0, 3.0 and 3.5 installed? Just the runtime is not enough.