Manyally Register ASP.NET with IIS
If IIS is installed or enabled after ASP.NET, you will need to manually register ASP.NET with IIS in order for your
.NET application to work.
Run the Command Prompt (cmd.exe) as an administrator.
Navigate to the appropriate .NET Framework location. (e.g. C:\Windows\Microsoft.NET\Framework64\v4.0.30319)
Run aspnet_regiis.exe -i