How to handle ASP.NET application error that occurs on application start and transfer & display error in MVC view?

Question

I know that ASP.NET MVC has error filter attribute to handle specified error type. However, this feature cannot catch any error that occurs when application start. Therefore

Answer 1

The reason why Request and Response objects are null inside your Application_Error event is because the Application_Start event is not associated with any user, therefore you cannot redirect from it. Only the Application and Server built-in objects are available. Referencing the Session, Request, or Response objects would cause an error.

One workaround is to use try/catch and in the catch block log the error and set some global variable which indicates that something went wrong during application startup. Later on Application_BeginRequest you could check this variable and redirect accordingly.