Article ID: 2019689 - View products that this article applies to.
You have a Web site that is hosted on Internet Information Services (IIS) 7.0 or 7.5. When you browse to dynamic content in the Web site by using a Web browser, you may receive an error message that resembles the following:
This error occurs because the HTTP Handler configured to handle the request has certain preconditions set, but its Application pool does not meet some or all of these preconditions. This causes the static file handler to be used to process the request instead. The processing of the request then fails and the 404.17 status returned because the request is for a dynamic resource and not a static one.
For example, consider the following handler mapping:
In this case, a 404.17 error is returned if the *.aspx resource being requested from the site is handled in an Application pool that is not running in Classic Mode, is not 32 bit, or is not running the 2.0 version of the .NET Framework. In order for the resource to be served correctly in this example, all 3 pre-conditions must be met. Specifically, the application pool hosting this resource would have to be configured for Classic Mode, it would need to be configured to use the 2.0 version of the .NET Framework, and it would need to be set for 32 bit applications.
To resolve this issue, configure the Application Pool hosting the application to meet all of the pre-conditions set for the Handler.
The information in this section is meant to help identify which handlers are configured for the web site and application mentioned in the error, as well as help identify the pre-conditions that are configured for that handler.
The following commands can be used to identify the handlers configured for the Web Site listed in the output of the error.
List Application Pool
The following commands show how to determine what application pool the application is running in, and then list the preconditions configured for that application pool.
This command will output the handlers configured for the specific application in the default web site.
In the case of ASP.NET there may be many handlers configured for a *.aspx resource. In some cases, the handler may just need to be changed to match the application pool the application is running in. Below is a list of the different ASP.NET 2.0 Handlers with their various pre-condition settings.
ASP.NET 2.0 Integrated Mode 32/64-bit Handler
<add name="PageHandlerFactory-Integrated" path="*.aspx" verb="GET,HEAD,POST,DEBUG" type="System.Web.UI.PageHandlerFactory" preCondition="integratedMode" />
ASP.NET 2.0 Classic Mode 32-bit Handler
<add name="PageHandlerFactory-ISAPI-2.0" path="*.aspx" verb="GET,HEAD,POST,DEBUG" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v2.0.50727\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv2.0,bitness32" responseBufferLimit="0" />
ASP.NET 2.0 Classic Mode 64-bit Handler
<add name="PageHandlerFactory-ISAPI-2.0-64" path="*.aspx" verb="GET,HEAD,POST,DEBUG" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework64\v2.0.50727\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv2.0,bitness64" responseBufferLimit="0" />