I followed your directions but keep getting the following error: Method Not Allowed
The requested method POST is not allowed for the URL /form_ac.asp. Can anyone tell me what's wrong?

You can try this:

Go to Start->Control Panel->Administrative Tools->Internet Information Services. Then from the window that pops up, right-click over the name of your website (you can find this under the 'Web Sites' folder) and click 'Properties'. Select the 'Home Directory' tab, and click the 'Configuration' button. An "Application Configuration" window will now open. From the Application Mappings, double-click '.asp' extension row. An "Add/Edit Application Extension Mapping" window will now open. Make sure that 'Limit to' input field has following values listen in it:

GET,HEAD,POST,TRACE

Now, click 'Ok' and you are done. Let me know if this works out for you.

Good luck!