I have Win XP pro on all my PCs.
0. Login as administrator user.
1. Go to Start > Settings > Control Panel > Add or Remove Programs > Select "MSXML 4.0 SP2 KB954430" installation and click Remove button.
2. Go to %SystemRoot%\System32 and select MSXML4.DLL and MSXML4R.DLL files and delete them.
3. Go to Microsoft Download Center.
I went to Google and typed "KB954430 download" and clicked on Microsoft link (first link).
This should open
"Security Update for MSXML 4.0 Service Pack 2 (KB954430)" web page.
http://www.microsoft.com/downloads/...f69-83d0-932c430abd14&displaylang=en

Click DOWNLOAD button on this page to download msxml4-KB954430-enu.exe file.
Use this exe to install KB954430 update.

4. Go to %SystemRoot%\System32 folder. You should see MSXML4.DLL and MSXML4R.DLL files.