According to Microsoft, this is one of several possible error codes one can receive when using the Windows Update or Microsoft Update web site. In most cases, these errors are caused by temporary issues caused by very slight interruptions in communications between the computer to be updated and the update to be downloaded. These issues are generally self-healing. Before you try the troubleshooting methods in this article, try exiting the Windows Update site, waiting 10 to 15 minutes and start Windows Update again, and check for updates. You can also let Windows Automatic Update install the updates on its usual 24-hour cycle. You may encounter temporary connection-related errors when you use Windows Update or Microsoft Update to install updates
EDIT: Once again Shawn was quicker than me on the keyboard.