Windows Installer Corruption

The Windows Installer in Windows XP becomes corrupted when installing Norton Internet Security 2003 or 2004. When installing subsequent applications using the windows installer, the installer hangs where it would usually be ‘generating script options for action…’ Any ideas on how to recover the installer? Looked on Microsofts site and the only fixes I can find are for 2000/NT/98/Me etc. that will upgrade there installers from V1 to XP’s V2…