HTTP error 404.17 profiling ASP .NET 1.1 on IIS 7

Category: Troubleshooting & error messages
Date: 17 Jun 2009
Product: ANTS Memory Profiler
When profiling an ASP .NET 1.1 web application hosted in IIS version 7, the following error will be displayed in the browser:

HTTP Error 404.17 - Not Found
The requested content appears to be script and will not be served by the static file handler.

The cause of this problem stems from ANTS Profiler not configuring the application pool it creates for profiling ASP .NET applications in a way that will install the ASP .NET 1.1 handlers.
This problem will be addressed in a future version. If it is necessary to profile the application, then installing the ASP .NET 2.0 handlers will solve the problem, the side-effect being that the web application will load the .NET 2.0 runtime instead of the 1.1 runtime, which may cause undesired side-effects.

To install the .NET 2.0 handlers on your website, open a command prompt in "Administrator" mode and run
cd \
cd %systemroot%\microsoft.net\framework\v2.0.50727\
aspnet_regiis -i

This should not affect the normal runtime environment as the ASP .NET application pool will still use the ASP .NET 1.1 handlers as normal when the application is not being profiled.

Background:
=========
When configuring an application pool to run ASP .NET 1.1 applications, the handlers need to be mapped to the .NET version 1.1 runtime. In order for this handler mapping to succeed, the "runtimeVersionv1.1" precondition must be met. This precondition is set by the application pool configuration, and ANTS Profiler is not detecting ASP .NET 1.1 applications and setting the application pool up in the proper way for profiling ASP .NET 1.1. If the application pool was configured as follows, the error would not occur during profiling.

    <applicationPools>
      <add name="RGTestAppPool" managedRuntimeVersion="v1.1" managedPipelineMode="Classic" />
    </applicationPools>

ANTS Profiler is not setting the managedRuntimeVersion attribute, so the application pool is running on the .NET 2.0 runtime instead of the 1.1 runtime.