Hi FZRR,
To my knowledge, the latest update or service pack of Windows XP is Service Pack 3. please refer to the Windows lifecycle fact sheet:
http://windows.microsoft.com/en-us/windows/lifecycle
And also, as can be seen in the sheet, the support of Windows XP has ended at April 8, 2014.
If you purchase Windows XP from Microsoft or a reseller, you will get a installation CD, you can insert it into your CD-ROM to install Windows XP. Of course, you can copy all files from the CD to your local disk, then start the installation process from
Windows Explorer.
But if you don't have a CD, you can download the it from the
Microsoft Download Center website, and then install it manually.
By the way, this is the forum to discuss questions and feedback for Microsoft Office client. Since your query is directly related to Windows XP, I would suggest you to post in the forum of
Windows Client, where you can get more experienced responses:
http://social.technet.microsoft.com/Forums/windows/en-US/home?forum=itproxpsp
The reason why we recommend posting appropriately is you will get the most qualified pool of respondents, and other partners who read the forums regularly can either share their knowledge or learn from your interaction with us. Thank you for your understanding.
Regards,
Ethan Hua
TechNet Community Support
It's recommended to download and install
Configuration Analyzer Tool (OffCAT), which is developed by Microsoft Support teams. Once the tool is installed, you can run it at any time to scan for hundreds of known issues in Office
programs.