If Internet Explorer (IE) detects an error message from the web server less than 512 byte, it shows it’s own “friendly” error message.  As a web developer you should turn off the default friendly error page setting on IE.  It will help tremendously when debugging simple HTTP issues.  For more complex issues I suggest the excellent free tool Fiddler).

To change the setting:

  • Tools –> Internet Options –> Advanced Tab
  • Browsing –> Show Friendly Http Error Messagesimage

Before with it on:image

Here it is with the option turned off:image

This is a simple HTTP 404 example, but it clearly states the problem.