Vs. Net open the project and prompt that the solution is not Asp.net 1.1

First, declare that there are various causes of system errors. This solution is only applicable to one reason and is not universal.

After installing the system today and configuring everything, open the vs project and suddenly prompt that it is not ASP. net1.1 version, I was wondering, obviously 1. 1. I checked a lot of information online and didn't find out why. I went to the Microsoft official website to see the solution, but he said (ASP in the Web service extension under IIS. net v1.1.4322) I cannot find the content in some steps on my computer.
Solution: under DOS, find "C: \ WINDOWS \ Microsoft. net \ framework \ v1.1.4322 "directory. Enter" aspnet_regiis-I "in the directory and press Enter. In the Web service extension, you can find what Microsoft officially says, then, "allow" the extension.
OK. Solve the problem.