En direct de MS :
By default, Internet Explorer 6 is preinstalled in all versions of Windows XP and cannot be uninstalled. To provide computer manufacturers more flexibility in configuring desktop versions of Windows XP, Microsoft has made it possible for OEMs, administrators, and users to remove user access to Internet Explorer while leaving the Internet Explorer code intact and fully functional to make sure the functionality of programs and operating system functions that rely on it. For example, Windows XP supports an "IEAccess=off" switch in the Unattend.txt file, and Internet Explorer has been added to the Add/Remove Windows Components section of the Add/Remove Programs tool in Control Panel. This does not reinstall Internet Explorer.
http://support.microsoft.com/defau [...] us;Q318378
On peut réinstaller et/ou réparer IE6 sous XP mais pas le supprimer.
Pierre.