Description of Hypertext Transport Protocol Error Messages

ID: Q218155

The information in this article applies to:
IMPORTANT: This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore it if a problem occurs. For information about how to do this, view the "Restoring the Registry" Help topic in Regedit.exe or the "Restoring a Registry Key" Help topic in Regedt32.exe.

SUMMARY

This article describes the use of friendly Hypertext Transport Protocol (HTTP)-status error messages.


MORE INFORMATION

WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

For information about how to edit the registry, view the "Changing Keys and Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it. If you are running Windows NT, you should also update your Emergency Repair Disk (ERD).

In Microsoft Internet Explorer 4, when the Wininet.dll file cannot resolve a request, it displays an embedded Hypertext Markup Language (HTML) error message and a non-descriptive definition (for example, "Navigation Canceled" or "Unable to retrieve Webpage in Offline mode".) These error messages are a resource (res:) of the Shdocvw.dll file. A resource is HTML code that a program uses for display purposes that is embedded in a dynamic link library (DLL) file. In Internet Explorer 5, these error messages are stored as a resource of the Shdoclc.dll file. When the error message is received it is replaced with a corresponding HTML template, which can contain any of the following types of information:

The friendly HTTP-status error messages are stored in the following registry key: 

   HKEY_LOCAL_MACHINE\Software\Microsoft\Internet Explorer\Main\ 
      ErrorThresholds
Internet Explorer 5 provides a replacement for the HTML template for the following friendly error messages:

400, 403, 404, 405, 406, 408, 409, 410, 500, 501, 505

There is a name value pair (for example, "404", 128) for each of the errors. The first value is the error code. The second value is the byte size value used by Internet Explorer 5 to detect when it should replace error messages with its own. Therefore, when the Internet Explorer 5 version of the Wininet.dll file obtains an HTTP error message, the Wininet.dll file determines if the HTML content attached to the HTTP error is a well designed Web page. This is based on the size of the page. The threshold value in the registry is evaluated for each error. If the Web page is small enough, it gets rejected, and the friendly HTTP-status Web page is displayed.

The HKEY_LOCAL_MACHINE key stores the computer's default values. The same key and value can be set in the HKEY_CURRENT_USER key to override the HKEY_LOCAL_MACHINE values on a per-user basis.

To disable friendly HTTP-status error messages, follow these steps:
  1. Click Start, click Settings, click Control Panel, and then double-click Internet Options.


  2. Click the Advanced tab.


  3. Click the Show friendly HTTP error messages check box to clear it.


  4. Click OK.


NOTE: Turning off friendly HTTP error messages disables only friendly HTTP error messages for HTTP error messages returned by the server (listed above). There are other friendly error messages that cannot be disabled. For example, DNS error messages occur when Internet Explorer cannot find a server. In this case, there is no page to replace so Internet Explorer 5 always displays a friendly "Page cannot be displayed" error message.

Additional query words: 


Keywords          : msiew95 msient msiew98 
Version           : WINDOWS:5
Platform          : WINDOWS 
Issue type        : kbinfo

Last Reviewed: May 6, 1999