Updates never install on my Windows Vista anymore. How do I fix it?

I got my new laptop from Dell 4 weeks ago, and for the past 2 weeks, none of the Windows Updates have successfully installed. I get 1 of 2 different error codes each time. I tried the steps in the troubleshooting and I tried two other steps from other message boards, but nothing has worked. Not even manually installing them fixes the updater problem. What's another way to fix this? Thanks.