I found solution,
This occurs when IIS has lost its mappings to ASP.NET
1. Open a command prompt
2. Change to the following directory (or whatever version of the .NET Framework you are using): C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727
3. Run the command "aspnet_regiis.exe -i". This may take several minutes and will report the success/failure of the process.
Sometimes It does not work, then reinstall IIS.