Clean Install of ColdFusion MX 6.1 on 64 bit windows (IIS 6.0) succeeds but displays internal server error 500 on page requests

I just spent an afternoon trying to install Coldfusion MX 6.1 on Windows Server 2003 Enterprise R2 64bit. I got the installer to run fine by adding coldfusion-macr-win.exe as an exception to the Data Execution Prevention (DEP) feature (under system properties->advanced->performance->settings->Data Execution Prevention) and the install went smoothly. After the installer finished, I checked to verify that the coldfusion IIS service extension was allowed to run in IIS (start->programs->administrative tools->IIS Manager->Web Service Extensions) and that all seemed to be enabled by default. But when the configuration wizard was launched in the browser, I got a big 500 internal server error from IIS. I double checked all the IIS settings and everything was setup fine, but I couldnt even hit a static .html file in IIS anymore.

I ended up uninstalling coldfusion and then I even removed IIS and re-added it. From there, I tested that I could hit static .html pages in the default site, and I could just fine. Performed the coldfusion install again and boom, IIS would no longer serve up any pages, not even the static HTML. So then I did some digging and found a post by Ben - Connecting ColdFusion MX 7 to 64bit IIS 6 which ended up solving my problem.

It turns out that IIS 6 on 64 bit windows runs only 64bit processes by default. The coldfusion extension is a 32 bit service, so it hosed up the whole IIS 6 service when it was enabled. I was able to enable 32bit extensions as described in the technet article Configuring IIS to Run 32-bit Applications on 64-bit Windows (IIS 6.0), and after an iisreset coldfusion was working again and I was able to complete the install.

I dont know how stable coldfusion will be in this kind of a setup, but at least you can get coldfusion running if you need it.