If you receive Windows Update error 0x80243004 when Windows Update checks for new updates, the error means that the notification icon for Windows Update has disappeared. This prevents Windows Update from installing new updates. Follow these instructions to show the icon and continue installing updates.
In the notification area, at the far right of the taskbar, click the Show hidden icons button, and then click Customize.
In Notification Area Icons, under Icons, scroll down to find Windows Update, click the drop-down list next to it, click Show icon and notifications, and then click OK.
Go to Windows Update and check for updates again.
Error codes this applies to: