[asp.net] How to add ASP.NET 4.0 as Application Pool on IIS 7, Windows 7

Open a windows command line. Switch directories to C:\Windows\Microsoft.Net\Framework\v4.0.xxxx where the x's are the build number. Type aspnet_regiis -ir and hit enter. This should register .Net v4.0 and create the application pools by default. If it doesn't, you will need to create them manually by right-clicking the Application Pools folder in IIS and choosing Add Application Pool.

Edit: As a reference, please refer to the section of the linked document referring to the -i argument.

http://msdn.microsoft.com/en-us/library/k6h9cz8h.aspx