You may receive an error message when you search for available updates on the Windows Update Web site or on the Microsoft Update Web site Check this link
0x8024402C or 0x8024502d error codes
To resolve these errors, remove characters from the proxy exception list, and then clear the proxy cache. To do this, follow these steps:
1. Open Internet Explorer.
2. On the Tools menu, click Internet Options.
3. Click the Connections tab, click LAN Settings, and then click Advance.
4. Delete any entry in the Exceptions section.
5. Quit Internet Explorer.
6. Click Start, click Run, type cmd, and then click OK.
7. Type the following commands.
Press ENTER after each command.
• proxycfg -d
• net stop wuauserv
• net start wuauserv