For those who experience problems with updates for vista, there is only one
sure way of overcoming this without all the hassle.
1- delete the main partition, then create a partition, then reformat the
drive, usually C:\
2 - Install Vista
3- DO NOT install anything at all, no firewall or antivirus, just let
windows firewall and windows defender take care of things for now.
4- Update vista, continue to update/restart and update until there are no
more updates available.
5- place a shortcut on the desktop for " windows update " (Control
Panel/windows update-"right click, send to desktop-create shortcut)
6- install your third part software one at a time, after each install of a
program, run the vista update, if it comes back stating there are no updates
available you know the prog you just installed is fine.
7- Continue using this method after every install of new software.
8-If after installing a specific software prog you get the message "Windows
is UNABLE to check for updates, then you know the last piece of software you
installed is not compatible with vista, even if it does state that it is. In
this case uninstall the offending software and do a system restore to a
point BEFORE you installed the offending/incompatible software. Run windows
update again after the system restore.
9- If you continue to use this method you will never encounter any "unable
to install" update errors.
There are quite a few third party firewalls and anti-virus programs and
hundreds of other software that will block vista update as they consider
part of the update to be a virus or an incoming threat.
Myself, I use Sunbelt Personal Firewall and Bit defender-2009 Antivirus.
Please note Bit defender WILL disable Windows-Defender) This is quite
acceptable as Bit defender has built in Anti-Spyware, Anti-Malware plus of
course Anti-Virus.

If this information helps at least one person from the headaches and
frustration caused by third party software then it is well worth my writing
this post.

Vangellis
MCP,MCTS,MCPD,MCIPT,MCA,MCSE,MCSD,MCDBA