How can I show detailed ASP errors?

By default, Windows Server hides application errors from your website. You can override this by adding the following inside a 'web.config' file that will cause IIS to output any errors to your browser:

<configuration>
  <system.webServer>
    <httpErrors errorMode="Detailed">
    </httpErrors>
  </system.webServer>
  <system.web>
    <customErrors mode="Off">
      <compilation debug="true">
      </compilation>
    </customErrors>
  </system.web>
</configuration>