ASP.NET Version 4 Framework, External component has thrown an exception

My web application under develoopment was running just ok until a few hours ago without any change from my side, I started receiving the error "External component has thrown an exception.". The error message is the same even if I open my other web applications which I have not touched for a long time. Any idea what causing this. See error below:

External component has thrown an exception.

An unhandled exception was generated during the execution of the current web request.

Information regarding the origin and location of the exception can be identified using the exception stack trace below. [HttpException (0x80004005): External开发者_C百科 component has thrown an exception.]

System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +9036040

System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +97

System.Web.HttpRuntime.ProcessRequestInternal(HttpWorkerRequest wr) +258

Few things you can try to figure out the issue. I don't exactly what might be the issue though.

1. Try to attach another instance of Visual studio to debug the exact cause. Detailed step by step process is listed in the following link.

http://connect.microsoft.com/VisualStudio/feedback/details/653950/external-component-has-thrown-an-exception

1. Check you web.config it has changed from your previous versions. Once I updated to framework 4 it messed up the layout and caused an issue but not the same as yours.