When your clients access the Windows Update Web site from Windows XP, they see one of the following errors in the upper-right corner of the Web page:
\[Error number: 0x80244017\] \[Error number: 0x80244018\] \[Error number: 0x80244019\] \[Error number: 0x8024401B\] \[Error number: 0x80244021\]NOTE: You can check their %SystemRoot%\Windowsupdate.log file.
Windows XP uses WinHTTP or BITS (Background Intelligent Transfer Service) to download updates. The above errors indicate that that the proxy or firewall denied the client access to the Windows Update site.
Make sure that your proxy or firewall allows anonymous access to the Windows Update site, including the following:
http://download.windowsupdate.com https://*.windowsupdate.microsoft.com http://*.windowsupdate.microsoft.comNOTE: You could implement SUS (Software Update Services) so you clients didn't have to access the Windows Update site.