\\SERVER\Clients\Setup\setup.exe with Windows Vista Error

Question

I added the first Vista client to an SBS 2003, SP1 domain.  Until now, all clients were WinXP, SP2.  Office 2003 is installed on the XP clients, and the Vista client, which may not be pertinent to this problem.
As is normal, "\\SERVER\Clients\Setup\setup.exe /s SERVER" is executed when a user logs on to any domain client.  On the Vista client, I always get the dialog -- regardless of the account privilege -- asking for permission to run Setup.exe.  It is annoying.  Occasionally, the Program Compatiblity Assistant will appear and advise there's a known compatiblity issue with Setup.exe.  It points to KB article 926505 for resolution.  The title of the KB is, "Windows Small Business Server 2003: Windows Vista and Outlook 2007 compatibility update."
When I run the SBS2003SP1-KB926505-X86-ENU.EXE fix, I get the error:  "This update cannot be installed.  Either it is already installed as part of an existing service pack, or it requires a more recent service pack.  For more information, see the systems requirements on the download page."
I installed Windows Server 2003 SP2 and run the KB926505 fix, but I get the same error  "This update cannot be installed.  Either it is already installed as part of an existing service pack" After a reboot of te SBS server the same  problem on the Vista client, I always get the dialog -- regardless of the account privilege -- asking for permission to run Setup.exe.  It is annoying.  Occasionally, the Program Compatiblity Assistant will appear and advise there's a known compatiblity issue with Setup.exe.  It points to KB article 926505 for resolution.
The problem is Windows Vista Business, because all windows XP clients have no problem at all.

Answer 1

PNP,
You do not say whether if you accept the permission dialog whether the setup continues or not, but the short answer to the question revolves around UAC.
Remember that EVERY user (except the actual Administrator account) has only Standard user rights regardless of group.  When a task that requires Admin rights is executed, one of three things will happen: 1) If you are THE Administrator, then your task will continue.  2) If you have Admin rights, you will be prompted that a process is trying to use elevated rights and ask for permission, or 3) If you are a Standard user, you will either be denied flatly or prompted to supply credentials.  Which of these happen depend on GPO settings, but the default is to prompt.
In any event, I believe that this is what you are running into, and is one of the big feature improvements in Vista.  Yes, it can be a bit annoying (Try deleting an "All Users" icon from the Start Menu!) but is there to place one more barrier between virus and malware writers and your OS.
If it's TOO annoying to bear, you can turn off UAC by going into your profile and disabling it. (It requires Admin rights, of course. )  It is not recommended as you do a very effective job or nutering the Vista Security Model by doing so.
If it, of course, your choice.  we IT Admins have a lot more issues with this than the standard user, but for me, I gladly take the tradeoff because I worry a lot less about those few I HAVE to give Admin rights to.
Good luck!