Windows Update won’t work

I'm have problems Windows Update. The site tell me that there are alot of critical updates. When I click on the “install” button, it takes ages to download them and then says it’s unable to install them and I should try again. How can I get them on to my system? The site has worked fine before.

It’s likely your catalogue file is damaged, but it’s easy to fix. Go to Start > Run, and type CMD. Then type net stop cryptsvc, and press [Enter] – this stops the Cryptographic Service. Next, type ren %systemroot%\system32\ catroot2 oldcatroot2 and press [Enter] again, then type net start cryptsvc to restart the service. Windows Update should now work – and one of the updates you’ll download should prevent this problem reoccurring.