Some people are still using Windows XP Pro which only installed IIS 5.1. When you try to run ASP.NET 4.0 web application, you might meet the following error message:
Server Error in ‘/TestWeb’ Application.
Configuration Error Description: An error occurred during the processing of a configuration file required to service this request. Please review the specific error details below and modify your configuration file appropriately.
Parser Error Message: Unrecognized attribute ‘targetFramework’. Note that attribute names are case-sensitive.
Line 14: Line 15: <system.web> Line 16: <compilation debug=“true” targetFramework="4.0" /> Line 17: Line 18: <authentication mode="Forms">
Run the following command:
The location where aspnet_regiis.exe resides: