IIS7 & ASP Classic - 500 - Internal Server Error

I'm trying to get ASP Classic working with IIS 7, but am having no
luck.

After being unable to get my site working, I tried a simple test page:

<?=2+2?>

But I get the same 500 error as with the other pages on my site. File
and directory permissions appear to be set correctly, ASP Classic is
installed and mapped correctly. I'm at a complete loss.

Thanks in advance for any help.