It possible that you haven’t got Classic ASP support installed in IIS. To do this in Windows 7 follow the steps below;

How to enable Classic ASP support on IIS for Windows 7

Installing Classic ASP support

1. Goto Control Panel -> Programs and Features

2. Select from the left navigation bar

   

3. From the Windows Features dialog expand Internet Information Services -> World Wide Web Services -> Application Development Features and tick the option ASP this will also tick ISAPI Extensions if not already ticked (see image).

   

Configuring IIS Web for Classic ASP

1. Open Administrative Tools -> Internet Information Services (IIS) Manager and select the website you wish to configure.

2. In Features View under the IIS section select Handler Mappings check the existing mappings list that appears for a handler that points to *.asp if one doesn’t exist select Add Script Map from the right hand navigation bar.

3. Fill in the options as per the below image

   

   IMPORTANT If using 64-bit and want to enable 32-bit support you may wish to use the 32 bit equivalent ISAPI DLL. See Dee’s answer to How to enable ASP classic in IIS7.5

4. Select the Request Restrictions button to open Request Restrictions dialog. The three images below detail the values that should be configured if not already set.