Why is my site trying to load the 32 bit aspnet_filter.dll even when 'enable32BitAppOnWin64' is set to False?

Question

I was developing an ASP.NET MVC web app on Windows XP and Visual Studio 2008 (using the Visual Studio web server). I recently installed Windows 7 64 bit Ultimate edition, IIS 7.5 and migrated my app using appcmd.

If I set the flag enable32BitAppOnWin64 == false on my application pool my application works fine. As soon as I set it to true (since I want it to run in 64 bit) it throws this exception:

Screen Shot of error

HTTP Error 500.0 - Internal Server Error
Calling LoadLibraryEx on ISAPI filter "C:\Windows\Microsoft.NET\Framework\v2.0.50727\\aspnet_filter.dll" failed

If I go and delete all ISAPI filters but leave ASP.Net_2.0.50727-64 then this error goes away.

How do I resolve this?

Answer 1

Your key is in the path mentioned in the error:

C:\Windows\Microsoft.NET\Framework\v2.0.50727\\aspnet_filter.dll

Notice there is an extra slash in the path. At an elevated command prompt, navigate to ../Framework/v2.0.50272 directory and run the following command:

aspent_regiis -r

Alternatively, use IIS to modify the correct path of the filter.

So no magic dust needed...you just need to register the right path. :)