I have ONE XP machine on which I have not yet installed SP3.  
That machine has an nVidia chipset on the motherboard, and I 
have not been able to find a driver for its IDE controller that 
is compatible with SP3.  It gets most of the way through the 
install, reboots into the new regime, and discovers there is no 
hard drive it can talk to....


On 12 Oct 2009 at 16:21, Computer9f wrote:

> SP3 installs NAP (Network Access Protection) to block your PC from
> certain network areas unless you accept and comply with software
> requirements designed to protect the the vendor/provider/network
> owner.


  NAP is Microsoft's implementation of a class of features 
called Network Access Control (NAC), and specifically is 
integrated with Active Directory for management of medium-to-
large networks.
  I work at a college,  We have a lot of machines on the campus, 
in faculty offices and in student labs, which belong to the 
college and are administered and maintained by our IT staff.
  We also have a lot of faculty -- especially part-time who are 
not allocated a machine by the college -- and students who bring 
personal laptops onto the campus and use a wired or wireless 
connection to get access to the Internet.  Historically, our 
worst virus problems have originated when an infected "visitor" 
machine has been connected to the campus network and proceeded 
to find and infect other vulnerable systems....

  NAC generally (and NAP specifically if we were a 100% Windows 
environment) lets us specify rules like "PC must have latest 
version of any of these dozen antivirus packages, with current 
updates", and deny machines which fail that test the opportunity 
to share any ifections they carry with our other network users.  
It's a tool for *protecting our network and all of the other 
users on it*, not for Microsoft or some other Big Brother to 
decide that user X is not allowed on our network.  In fact, the 
usual action is not an outright ban, but temporary assignment to 
a network segment from which one can download or update 
antivirus software and then "re-apply" to join the "normal" 
network.

  This requires a fair bit of back-end work by network 
administrators.  It's not something that's going to have any 
effect on your home network or Internet access through a 
residential ISP.  If you are in an environment where it is used, 
you will likely be told that you MST have SP3 installed.

  So far as I can see, it's not any reason to avoid installing 
SP3.

David Gillett
CISSP CCNP MCSE

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