The custom error module does not recognize this error

Last Published: April 25, 2020

Error Message

When ArcGIS Server services that are secured with token-based authentication are running on Internet Information Services (IIS) 7, requesting the service WSDL in browser may display the message:

"The custom error module does not recognize this error."


This error may occur when the ArcGIS Server Web services are installed on IIS 7 (Windows Vista or Windows Server 2008). The error displays when the service is secured and requires a token to access the service. The browser or other client may display the message when trying to access the WSDL or otherwise requesting data from the service.

The cause of the error is that the ArcGIS Server Web service is returning an error code of 499, with a message of "Token required". On IIS 7, the error code 499 is not registered as a valid error code by default. When the browser is not running on the Web server machine, IIS returns "The custom error module does not recognize this error" instead of the actual code and token-required message. For a browser running on the IIS Web server machine, the server, by default, returns the original 499 error code and token-required message.

Solution or Workaround

Add the error code to IIS 7 so that it displays the token-required message to clients. Users must still acquire and use a token to access the secured service. For details on tokens, contact the ArcGIS Server administrator or see the ArcGIS Server Help.

To add the error code to IIS 7:

  1. Create a simple .htm page for the error message. Use an HTML editor, such as Visual Studio or Dreamweaver, or even a text editor such as Notepad. It may have just a <title> and <body> with a short description, such as 'This GIS service requires a token for access. See the ArcGIS Server Help for information on using tokens for secured services. Save the .htm file in a permanent location on the server.
  2. Click Start > (All) Programs > Administrative Tools, and click on Server Manager. The Server Manager application opens.
  3. Click Roles, and on the right side, scroll down to Web Server (IIS), and under the Role Services list, check that the HTTP Errors item is Installed. If not, click Add Role Services and enable the HTTP Errors role service.
  4. On the left-hand side of Server Manager, expand Roles, expand Web Server (IIS), and click on Internet Information Services (IIS) Manager. In the Connections column just to the left of the middle, click on the server name. The server's home page with settings links displays on the right side of the window.
  5. On the right side of Server Manager, double-click on Error Pages under the HTTP Features category. A list of error-codes and pages display.
  6. Under Actions in the right column, click Add..., and in the dialog box that opens, enter 499 for the code. Click the option for 'Insert content from static file into the error response', and type the path or browse to the .htm page created. Click OK to save the settings. Close the Server Manager.
  7. Open a browser on a computer other than the Web server, and request the WSDL for a token-secured service in a browser. For example:


    The custom error page created should be viewable.

Article ID:000010351

  • ArcGIS Server

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