To enable debugging, please do the following:
Make sure you have administrator privileges.
Make sure debugging is not disabled: run Internet Explorer and select Tools / Internet Options / Advanced tab. Un-check both Disable Script Debugging (Internet Explorer) and Disable Script Debugging (Other):
Click here to complete the 10-minute step-by-step guide to learn how to debug your web applications in record time.
Microsoft Visual Studio
IIS - Internet Information Server
PWS - Personal Web Server
Remote Components Setup
Microsoft Script Debugger
If in doubt, or if you get the error message "class not registered" when you start debugging, go for the Microsoft Script Debugger download. It is free, and it installs Active Script Debugging: