1. Find your PHP version. You will need to know the version when you download the ionCube loaders.
2. Download ionCube loader from: http://www.ionCube.com/loaders.php
Download this version: Windows (x86) — Windows Installer
Download this version: Windows (x86) — Windows Installer
3. Install ionCube loader to XAMPP at: C:\xampp\htdocs\ioncube
4. Open php.ini with your text editor. (Edit php.ini file on C:\xampp\php\php.ini)
The file is located at C:\xampp\apache\bin\ or C:\xampp\php\.
Add the following line before any other zend_extension statements.
Add the following line before any other zend_extension statements.
zend_extension = “C:\xampp\htdocs\ioncube\ioncube_loader_win_5.3.dll”
And Save this file.
5. Run (or restart) XAMPP, and open the folling link http://localhost/ioncube/loader-wizard.php
6. For security reasons we advise that you remove*** this Wizard script from your server now that the ionCube Loader is installed.
Remove this file ! http://localhost/ioncube/loader-wizard.php
Remove this file ! http://localhost/ioncube/loader-wizard.php
Sumber : http://support.open-realty.org/showthread.php?24689-installing-ioncube-on-Xampp.