Enabling ASP Error Processing (IIS 6.0)
The default Web site transfers the processing of Active Server Pages (ASP) errors to the 500-100.asp file (by default). If you create a new Web site, ASP errors return standard HTTP Status Codes (known as Default in IIS Manager. If you want to customize ASP errors, you can either map the 500-100 error to the 500-100.asp file or create an error-processing ASP file of your own. If you create an ASP error-processing file of your own, you must enable the custom error file through IIS Manager.
You must be a member of the Administrators group on the local computer to perform the following procedure or procedures. As a security best practice, log on to your computer by using an account that is not in the Administrators group, and then use the runas command to run IIS Manager as an administrator. At a command prompt, type runas /user:Administrative_AccountName"mmc %systemroot%\system32\inetsrv\iis.msc".
To enable ASP error processing by mapping to a URL