Web.Config weird section <customErrors>?

Question

I was looking at the ASP.Net web form tutorial here: on asp.net. This tutorial contains a section for custom errors, which is a bit strange for me.

<customErrors mode="On" defaultRedirect="ErrorPage.aspx?handler=customErrors%20section%20-%20Web.config"> <error statusCode="404" redirect="ErrorPage.aspx?msg=404&amp;handler=customErrors%20section%20-%20Web.config" /> </customErrors> 

Question: Can someone explain the query string parameter handler=customErrors%20section%20-%20Web.config" to defaultRedirect and redirect it ?

Does this syntax make special sense?

Answer 1

%20 are just URL encoded spaces. It sends the human-readable name of what is redirected to the error handler page in the query string.