Configuring cPanel to use FastCGI to server your web pages and PHP driven scripts can be easily done using EasyApache (Apache Update) that is built into the WHM side of cPanel.
The side effect of using the out of the box configuration with cPanel is that you will quickly run into "Internal Server Error" when you attempt to upload files via a php script, common ones being WordPress, IPB, PHPBB & VBulletin.
The error is caused by the FastCGI configuration,
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