Sign up for Office 365
Learn more about Office 365
I am not the world's expert on this, but I can tell you that Office 2013 desktop applications are not compatible with Windows XP, and it may be these that are tripping your installation up. I had a similar experience trying to install Office 365 from the web on a user's machine, based on a Microsoft web page that says Office 365 is compatible with Windows XP, so long as it has a particular Service Pack installed. Sorry I can't remember the exact details...Suffice to say, this advice does not apply to the Office 2013 desktop applications themselves. Extremely irritating, but true. I don't know what parts of OFfice 365 ARE compatible with XP...Perhaps this guidance was in reference to the Web applications, such as the in-browser Word and Excel applications? Either way, the desktop versions certainly are not XP compatible. And this is not made as clear as it could be Microsoft in my view.
The web based parts of Office 365 can run on just about anything with a newer browser, how ever the install is trying to install Office 2013, and that will only install and run on Windows 7 and 8.
Hope this helps