I installed a ASP.Net website on a Windows 2008 server, which is by default using IIS7. The website seems to work fine, but the post backs on my forms do not work. After a few hours of debugging, I realized that when I manually try to hit the WebResource.axd file in my browser (e.g. I type http://www.domain.com/WebResource.axd in the address bar), I get a HTTP 403 error (Access Denied).
I'm not quite sure where to look next and my Windows 2008 security knowledge is limited. How do I go about giving access to that file?
Navigate to your iis config folder. Typically: c:\windows\system32\inetsrv\config
and open applicationHost.config file. Then within file navigate to the <handlers> section and check that following line is present:
<add name="AssemblyResourceLoader-Integrated" path="WebResource.axd" verb="GET,DEBUG" type="System.Web.Handlers.AssemblyResourceLoader" preCondition="integratedMode" />
That is if you're running in integrated mode. Check that verb GET is specified.
If you are running in classic pipeline mode that this line should be present
<add name="AXD-ISAPI-2.0" path="*.axd" 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" />
If everything seems to be ok than look at your web.config in Handlers and Modules section and see if you have added <clear /> on the top of each. If you did then you have include add section in your web.config file respecting the order in of the handlers/modules specified in applicationHosting.config file.
Check your IIS logs - they should give a status code that has more detailed information about the error. Also, what is the nature of the error on the postback?
This is the error that I'm getting when doing a Postback:
WebForm_PostBackOptions is undefined.
To my knowledge that function is contained inside the WebResource.axd file, which led me to try it in the address bar, which how I know about the 403 error...
Not sure on that one, but it may be related to http compression in IIS. Also check that the file is accessible to the IIS User.
来源：https://stackoverflow.com/questions/123585/webresource-axd-giving-403-error-in-asp-net-post-backs-using-iis7