If you receive Windows Update error 8024402C while checking for updates, you might need to do one of the following:
? This error might be caused by a program running on your computer that is preventing Windows Update Services (SVCHOST) from accessing the Internet. Programs that might do this include firewalls, anti-spyware software, web accelerators, Internet security or antivirus programs. and proxy servers. If you have any of these programs running, you might need to turn them off while downloading and installing updates. Microsoft recommends you turn them back on after updating your computer. For more information, see Windows Update error 80072efd.
? If the computer is connected to a network at work, contact a network administrator. You probably receive updates using Windows Server Update Services (WSUS), a service that enables network administrators to deploy and manage updates for all computers on a network. For more information about WSUS, go to the Windows Server Update Services (WSUS) website.
? If your computer is usually connected to a network at work (for example, if you use a mobile PC but you are currently using it at home or at another location), you probably receive updates using WSUS and can not receive updates by connecting directly to the Internet or to another network, such as a home network. To solve the problem, connect to the network at work and try checking for updates again, or contact a network administrator.
? If the computer is connected directly to the Internet or to a home network (and never connected to a network at work), you might need to set Internet Explorer to automatically detect local area network (LAN) settings so Windows Update can go online to obtain updates. To do this, follow the steps below.
1. Open Internet Explorer by clicking the Start button , and then clicking Internet Explorer.
2. Click the Tools button, click Internet Options, click the Connections tab, and then click LAN settings.
3. Under Automatic configuration, select the Automatically detect settings check box, and then click OK.
If the problem persists after you have followed the steps above, see this Knowledge Base article on the Microsoft Help and Support website or go to the Windows Update Support Center website to request support by e‑mail.
Help and Support search term: WindowsUpdate_8024402C
This is yet another reason to hate vista. on Dec. 15 vista was doing an automatic update as it does every day and for some unknown reason it started setting off my antivirus alarm, it has never done this in the past. I was able to stop this by not allowing the update, but update has not worked since. I recieve an error message saying it's blocked. the number is 8024402c, I tried all the things it tells you to do in get help to no alvail, I even went as far as removing my antivirus software shutting down all security and then trying the update and it still does not work. Microsoft is of little to no help at all as I have tried everythig that can be found on all thier websites and still nothing. Is there any solution to this other than reinstalling the operating system, if I have to do that I think it would be better to go with another operating system. It's really TRUE Vista does really SUCK.

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