Service pack 3 - Microsoft Windows XP Professional

Microsoft Support for Windows Vista (with no service packs installed) ended on April 13, 2010, while support for Windows XP (without Service Pack 3 installed) ended on July 13, 2010. Windows 2000 support ended on July 13, 2010 as well.
There is no Service Pack 3 for the 64-bit version of Windows XP. If you're running the 64-bit version of Windows XP with SP2, you have the latest service pack and will continue to be eligible for support and receive updates until April 8, 2014.
If you are still running a version of Windows where support has ended, it means that version of Windows will no longer receive any updates from the Windows Update or Microsoft Update site. These updates are generally provided for security reasons to help protect the PC from harmful viruses, spyware, malware, and other malicious software. Windows Update also provides new drivers for your hardware that can improve the reliability of Windows.
Hackers love to take a security vulnerability in Windows and exploit it to their advantage. So, if a vulnerability is found in Windows XP or Windows Vista and you are not running the latest service pack, you will not be protected and will be at risk.

How Can I Tell What Service Pack is Installed?
Follow these steps to discover what Service Pack is installed:
1) Click on the Start Button
2) Right-click on either My Computer or Computer (depending on your Windows version)
3) Click on Properties
On this window, it should tell you which version of Windows along with which service pack is installed). It should also tell you whether you are running a 32 bit or 64 bit version of Windows.

Where can I download the latest Service Pack for Windows?
For Windows XP, click on the following link to download Service Pack 3

For Windows XP Service Pack 3 info, click below :-
http://windows.microsoft.com/en-us/windows/help/learn-how-to-install-windows-xp-service-pack-3-sp3

For Windows XP Service Pack 3 download, click below :-
http://www.microsoft.com/downloads/details.aspx?FamilyId=5B33B5A8-5E76-401F-BE08-1E1555D4F3D4

For Windows Vista, click on the following link to download Service Pack 2

Windows Vista Service Pack 2 info, click below :-
http://windows.microsoft.com/en-us/windows-vista/Learn-how-to-install-Windows-Vista-Service-Pack-2-SP2

Windows Vista Service Pack 2 download, click below :-
http://support.microsoft.com/kb/935791

Most users of Windows XP are using Windows XP service pack 2.
You can upgrade Windows XP service pack 2 by installing plain service pack 3.
This will upgrade and improve functionality to your current installation to Windows XP.
There are alot of versions of Windows XP Service pack 3 but i recommend downloading an official version from Microsoft's downloads center through the link below.

To after download is complete, install the file. Installation takes about 10 to 30 minutes depending on your system specifications.
If your current installation of Windows XP has too many errors, installation of service pack 3 may not be successful.
The solution to this is to reinstall your Operating System (OS) using your OS installation CD, then install Service pack 3.
How ever, OS re installation will erase all your data in your system partition so back up all your data.

To download an official copy of Windows XP service pack 3, follow this link:
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