I have bought an add-on that tells me I must have SP2 (Service Pack 2) installed. 
  Evidently it is a key update that should have been installed over 2 years ago automatically, but some PCs still don't have it.
  How do I check if I have it or not?
  What do I press?
  Sensible answers please - Point Hunters will be rated low!
 Windows XP - How do I check if I have SP2 installed?windows live  Press start and select RUN
  Type into the box - winver - and press enter
  A small box pops up telling you your windows version and which service pack you are on
 Windows XP - How do I check if I have SP2 installed?windows media player 11 internet explorer
 Push the "Windows" key + "Pause/Break" key at the same time.
  The little screen that pops up tells you right away what OS and SP you have loaded.
Ok. Righ click My computer goto propetries (or control pannel system propetires) it will be on the top right of the box that opens. something like 
  System;
  Microsoft Windows XP
  Media Centre Edition
  Service Pack 2
  Registered to;
  etc etc
Start%26gt; [Right click "My Computer"]%26gt; Properties.
  It should say directly to the right of the picture of a monitor with the Windows logo on it.
simple if you don't have the red security shield on the bottom and you didn't disable it, then you don't have SP2. Or you can right click on My Computer%26gt;%26gt;%26gt;and go to Properties%26gt;%26gt;%26gt;and check out what it says at the top of the General tab!!! It will tell you there!
dont know
very simple
  my computer right cilck
  properties
  display 
  system:
  windows xp professional version 2002
  service pack2
if you go to microsoft updates website it will scan your computer and tell you what updates you need. 
  http://update.microsoft.com/microsoftupd...
  this will take you straight there.
Right-click My Computer on your desktop or in the Start menu, select Properties. A window will pop up which, along with other information, will state which Service Pack you have installed. If you don't have Service Pack 2 installed, you can download it from the Microsoft website.
Double click on My Computer 
  On the top menu bar you'll see File Edit View Favorites Tools Help.
  Click on Help
  Scroll down to About Windows
  A Dialog box will open and under Microsoft Windows it will tell you what version of Windows is installed on your system and what Service Pack (SP) is installed.
Right click your "My Computer" Icon and select property. click general and you will see your system information.
click start thrn run and type winver you can also type winver at the command prompt that will tell you what your patched too.
Find "My Computer" (by clicking start or it is only your desktop)
  left click
  Select Properties
  General Tab
  And in my tab it says the following:
  Microsoft Windows XP
  Home Edition
  Version 2002
  *******Service Pack 2*********
  Yours should say service pack 2 if you have it installed. Have a nice day.
  Pablo
very simple when u switch you comp on , when it loads the first screen you will notice a row of dots going left to right if they are green you dont have it if they are blue you do have it !