Thank you for your response. IIS setup is as usual. Nothing special I have made. I havent installed Firebug for FireFox.

But the error is not only in FireFox, In IE it is throwing 'Sys' is undefined error and in ForeFox the data is not loaded but it doesnt throw any error. I have even tried reinstalling AJAX Extension, but it was of no use.

This is working for me on Windows 2003 server.

I just installed ASP.NET AJAX, it returned error 404 for scriptresource.axd. I went to website properties, Home Directory, Configuration, .axd Extension was missing. Clicked Add, set Executable to c:\windows\microsoft.net\framework\v2.0.50727\aspnet_isapi.dll, Extension to .axd, Limit to GET,HEAD,POST,DEBUG, checked Script engine, unchecked Verify that file exists.

 Now it is working fine and returns javascript code on Scriptresource.axd request.

 I was having the same problem, but I resolved it. I added compression code to the global.asax within the Application_BeginRequest. I believe the "content-encoding" header was being rewritten after the Application_BeginRequest sub executed, so I kept the compression code in the Application_BeginRequest sub, and moved the Response.AddHeader("Content-Encoding", "gzip") code to the Application_EndRequest sub, and now everything works perfectly.

Simply Add in Web.Config file :- Under <system.web> tag

<remove verb="*" path="*.asmx"/>

<add verb="*" path="*_AppService.axd" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>

</httpHandlers>

That will solve your problem.

i am also facing same problem with xp