These days it is not uncommon to have a server run multiple websites. One reason to do this is to have another site using a friendly name attached to your domain:
www.mycompany.com (the default site)
support.mycompany.com (the additional site)
Using the Internet Services Manager on Window NT or 2000, you can create a new site and associate it with an exisiting IP address or additional TCP port. All users requesting the new sites URL will be directed to the specified homepage for that site.
If you develop an ASP application for the new site, you will notice that nothing has changed, with one exception. Instead of getting a detailed error message telling you that your script failed at a particular line and column, you only receive the following:
Error 500: Internal Server Error
You probably realized that this is not a lot of help. And it is hard enough debugging our ASP scripts until .NET comes along. Well don't worry because I have a remedy.
When the new site is created, all of the errors that it produces are associated with either an HTML file or a preset message. It just so happens that when you default website is created, and additional application is installed. This application is called IISHelp. In IISHelp there is an ASP script, 500-100.asp, that provides the error messages that we are used to. When it is installed, it reconfigures the default website to call this ASP script instead of saying "Internal Server Error".
So all we have to do is make sure that our new site can reference this script as a URL. Then configure the website to call the 500-100.asp script. There are numerous ways that we can do this:
Create an IISHelp application on the new website
Copy the 500-100.asp script to the root or some other folder on the new website
I prefer the first method since any changes to the ASP page will be propagated to the new site. Then all that you have to do is set the error to point to this URL when it is fired.
Step 1: Create a new Virtual Directory for IISHelp
Step 2: Configure Custom Errors for the new website