Unable to install new updates on Windows Vista

I am using Windows Vista Ultimate and for the past few months, I have been unable to install any new updates available through Windows update. It appears to download the updates but never completed the installation giving me the error code: "8E5E03FA".
I have searched a lot for this; even went to my virus control live chat to see if the problem was there. I totally uninstalled my virus control, tried the Windows upgrade but still came up with the same problem.
Now can anyone here please give me some solution?
