Original title: Vista home premium Windows update

after clone and replace mi HDD in my gateway MD7818u, the system started fine, but microsoft security essential started to acting up, I uninstalled and when I try to install it again, it says there was an error and the installation stopped (error 0x80070643)

tried to use windows update it now take too long to load and then a new window appears saying: Windows Update cannot currently check for updates, because the service is not running. You maneed to restart your computer, I've verified the service is running and rebboted more than 3 times, and I got the same message any idea?