Error Installing Path of Exile

I downloaded the install exe. and went through all the prompts. When it's about to finish installing an error message pops up stating, "There is a problem with this Windows Installer package. A program run as part of the setup did not finish as expected. Contact your support personnel or package vendor." I don't know what this means or how to solve it. =(

My computer specs -

Microsoft Windows XP
Professional
Version 2002
Service Pack 2

Intel(R)Core(TM)2 Duo CPU
E6550 @ 2.33GHz
2GB of RAM
ATI Radeon HD 2400

Dear Jesus run Windows Update for God`s sake.

Where can I download PoE?