This error occurred mainly in earlier versions of the software. Please make sure you are using the latest version of Agent Ransack and FileLocator Pro.
Error: 3 indicates "Error related to PDF permissions."
The PDF reading functionality works by first converting the PDF to text but if the PDF has restrictions on copying text then it won't work. You can test this out by opening the PDF in Adobe Reader and seeing whether or not you're able to select a piece of text and copy it to, for example, a Word document.