The request failed with HTTP status 404: Not Found.(how to solve it)

he request failed with HTTP status 404: Not Found. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Net.WebException: The request failed with HTTP status 404: Not Found.

Source Error:

The source code that generated this unhandled exception can only be shown when compiled in debug mode. To enable this, please follow one of the below steps, then request the URL:

1. Add a "Debug=true" directive at the top of the file that generated the error. Example:

   <%@ Page Language="C#" Debug="true" %>

or:

2) Add the following section to the configuration file of your application:

Note that this second technique will cause all files within a given application to be compiled in debug mode. The first technique will cause only that particular file to be compiled in debug mode.

Important: Running applications in debug mode does incur a memory/performance overhead. You should make sure that an application has debugging disabled before deploying into production scenario.

Stack Trace:

[WebException: The request failed with HTTP status 404: Not Found.] System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall) +1785 System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters) +205 CMS.CustomEventHandler.WS.Community.UserInfoProvider.UpdatePassword(String username, String password, String email, String sitename) +153 CMS.CustomEventHandler.CustomSecurityHandler.UpdateUserPassword(String email, String username, String password) +136 CMS.CustomEventHandler.CustomSecurityHandler.OnAuthentication(Object userInfo, String username, String password) +160 CMS.SiteProvider.UserInfoProvider.AuthenticateUser(String userName, String password, String siteName) +272 CMSWebParts_Membership_LogonForm.Login1_LoggingIn(Object sender, LoginCancelEventArgs e) +219 System.Web.UI.WebControls.Login.OnLoggingIn(LoginCancelEventArgs e) +107 System.Web.UI.WebControls.Login.AttemptLogin() +77 System.Web.UI.WebControls.Login.OnBubbleEvent(Object source, EventArgs e) +101 System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +37 System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) +118 System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +168 System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10 System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13 System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3435

Version Information: Microsoft .NET Framework Version:2.0.50727.3603; ASP.NET Version:2.0.50727.3082