Failed updates error 57a and 643

Ok so i've gone through this so many times now and search Google over and over again, did things that other people have tried and none have had any success.
I have 7 important and 5 optional and none of the important ever complete.
As the title says errors are code 57a and code 643
so if anyone could explain in step by step what i can do to fix this and complete the install i would be much appreciated.
I've tried so many things i can't really remember what exactly i've done so i'l just try whatever goes up and then see if it works.

Welcome
Perhaps this MS article will help
When you try to install an update for the .NET Framework 1.0, 1.1, 2.0, 3.0, or 3.5, you may receive Windows Update error code "0x643" or Windows Installer error code "1603"

Thanks heaps rich that did work for one of the updates, any options for the others?

I find when that happens it helps to uncheck all but one and do them individually. I know it's a bind to do it that way but it does usually work.

Exbrit is correct. I always do a few at a time. When there are many updates to install all at the same time causes conflicts (because they reboot the computer) and problems.
This tutorial will show you how to change the update settings to notify. You will be notified when there is an update. This allows you to install one at a time. It is best (I find) to install the ones that contain smaller amounts of information (MB) first then the larger.
http://www.sevenforums.com/tutorials/2797-windows-update-settings-change.html (for Vista too)

Doing it one at a time will, also, show you the problem update. We can discuss that one when you know which it is. Sometimes in error updates are received more than once or should not even be received by you.

When they started failing i did try them one by one, they all get the same errors code 57a, they are security updates for infopath, outlook, powerpoint, word 2007,

There's free support from Microsoft for all update problems: https://support.microsoft.com/oas/d...ine&enty=PIDLESS&enval=815&st=1&wfxredirect=1

Change country at top right if applicable.