You receive error messages when you use Windows Update through a proxy server or a firewall

Symptoms

You may experience the following symptoms when you access or download from the Windows Update site through a proxy server or a firewall:

• You receive a "Cannot display page" error message when you try to access Product Updates.

• You receive a "Download and installation failed" error message when you try to download components. The download may not show any progress before it stops working.

• The site stops responding after the "Please Wait..." window appears and the site tries to initialize the Product Catalog.

Cause

This issue may occur if you are using any one or more of the following software programs:

• WinProxy - Otitis Software
  
  There have been fewer conflicts with WinProxy 3.0 than with earlier versions of WinProxy. There have been even fewer conflicts with Transparent Proxy instead of Classic Proxy (only applies to version 3.0).
  
  For additional information, visit the following WinProxy Web site:

  http://www.winproxy.net/

• WinGate - Deerfield.com
  
  Most conflicts occur with versions that are earlier than 3.0.
  
  For additional information, visit the following WinGate Web site:

  http://wingate.com

• Internet Gate - MaccaSoft
  
  MaccaSoft distributes Internet Gate software through BMT Micro, Inc. and Indelible Blue, but support is available through MaccaSoft.

This issue may occur for one or more of the following reasons:

• The proxy server caches the Windows Update page and its associated files. This behavior prevents the correct installation and initialization of the ActiveX control that the Windows Update Product Catalog uses to build on the client computers.

• Port 80 or 443 is closed. Windows Update requires both HTTP and HTTPS connections.

• The client computers are not configured to permit active scripting or the download and the initialization of ActiveX Controls.

Resolution

To resolve this issue, follow these steps:

1. Clear the proxy cache and configure it to exclude the Windows Update site.
   
   Note See your software documentation or contact the software manufacturer if you want help with the proxy server or firewall software configuration.

2. Open port 80.

3. Add Windows Update to the Trusted Sites Zone.

You must set the security settings in Microsoft Internet Explorer to Medium or lower for ActiveX files to correctly pass to your computer. When you lower the security settings, you affect only the Web sites that are listed in the Trusted Sites Zone of Internet Explorer. Your current security settings for all other Web sites remain as they are currently configured.

To set the security settings in Internet Explorer, follow these steps:

1. In Internet Explorer, click Tools, click Internet Options, and then click Security.

2. Click Trusted Sites Zone, and then click Sites.

3. Clear the Require server verification (https:) for all sites in this zone check box.

4. In the Add this Web site to the zone: text box, type http://*.microsoft.com, and then click Add.

5. Click OK.
   

6. Click Custom Level, and then click Enable for the following items:

   • Download signed ActiveX controls.

   • Download unsigned ActiveX controls.

   • Initialize and script ActiveX controls not marked as safe.

   • Run ActiveX controls and plug-ins.

   • Script ActiveX controls marked safe for scripting.

7. Click OK two times to exit Internet Properties.

For more information about Internet Explorer security configuration, click the following article number to view the article in the Microsoft Knowledge Base:

174360 How to use security zones in Internet Explorer