hxxp://www.mydigitallife.info/2007/12/19/fix-vista-winodws-update-error-code-80004002/ Error 0×80040002 is a standard COM error that related to E_NOINTERFACE, which means some COM DLL components on the system is not correctly registered, or has become corrupted. It’s probably due to this reason that Windows Update process cannot find the interfaces that its dependencies DLL exports. To solve and fix the 80040002 stop error on Windows Vista Update, try the following resolution to re-register the Windows Update related DLLs. Open an elevated command prompt, and type the following commands. Press ‘ENTER’ key after each command: regsvr32 wuapi.dll regsvr32 wuaueng.dll regsvr32 wuaueng1.dll regsvr32 wucltui.dll regsvr32 wups.dll regsvr32 wups2.dll regsvr32 wuweb.dll There may be some errors on registering on the DLL, which can be ignored. Once re-registered, check for updates again. In most case, Automatic Update will work almost immediately. If trick does not work, try to disable UAC. You can always re-enable the UAC once the Windows Update gets working again.