Why is my ColdFusion page returning a blank page to search engines?

I've done plenty of ASP.NET and PHP development, but I'm less familiar with how to track this sort of thing down in CF. My naive first angle of attack was to search for any reference to Google in any of the source code. No luck.

I'm running the site on IIS7. Google, Bing and Yahoo all apparently "see" nothing on my site.

Update: I ran Fetch as Googlebot and got the following:

HTTP/1.1 200 OK
Transfer-Encoding: chunked
Content-Type: text/html; charset=UTF-8
Server: Microsoft-IIS/7.0
Set-Cookie: CFID=1638251;expires=Sat, 14-Apr-2040 15:51:41 GMT;path=/
Set-Cookie: CFTOKEN=35688222;expires=Sat, 14-Apr-2040 15:51:41 GMT;path=/
Set-Cookie: LANGUAGEID=1;expires=Sat, 14开发者_如何学编程-Apr-2040 15:51:41 GMT;path=/
Set-Cookie: CFGLOBALS=urltoken%3DCFID%23%3D1638251%26CFTOKEN%23%3D35688222%23lastvisit%3D%7Bts%20%272010%2D04%2D22%2008%3A51%3A41%27%7D%23timecreated%3D%7Bts%20%272010%2D04%2D22%2008%3A51%3A41%27%7D%23hitcount%3D2%23cftoken%3D35688222%23cfid%3D1638251%23;expires=Sat, 14-Apr-2040 15:51:41 GMT;path=/
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Date: Thu, 22 Apr 2010 15:51:40 GMT

Use Google Webmaster Tools "Fetch as Googlebot" (its in labs) to see exactly what your server is returning to Google.

It turned out to be a convoluted application.cfm page.

It turns out it didn't work without cookies. Oh the joys of maintaining an old, rusty website! It's not the type of website (in terms of content and overall purpose) I would have expected to completely fail if cookies were disabled.

Being a newbie to CF, I mistakenly assumed that my simple "example.cfm" would only execute code on that page. I wasn't aware of the application.cfm. I checked for includes and saw nothing. That's when I hunted through the trace using IIS7's Failed Request Tracing capability. By comparing the googlebot request with a normal browser request, I became certain that nothing strange was happening at that level. There wasn't any rouge module being loaded that was messing with my request.