ASP.NET Compilation Error

Another common error I've found installing ASP.NET web services in IIS:

"Compilation Error - The compiler failed with error code 128"

This error has a simple solution: Just go to your .NET subfolder, for instance,

%SystemRoot%\system32\Microsoft.NET\Framework\

and type

aspnet_regiis -i

This will re-install and configure ASP.NET for IIS.