Today my windows update informs me that some updates were available to download+install. When Windows Update finished installing KB2770917 and restarting my laptops, i can see that the KB2770917 is failed to install. When it reaches 15%, the process stopped and then "reverting changes". I tried to look at the update's status in Update History section, it said that the update were failed.
Then i comeback to Windows Update to check whether there's a new updates available, and the KB2770917 (142 Mbytes) were always back in, as it never been downloaded before. Need help.