PRF, Outlook Profile File (.prf)
The PRF Settings file format
PRF files are used to store user profile information for Microsoft Outlook, an e-mailing program for Windows. They contain information of an Outlook user and different e-mail preferences. PRF files are used to store all settings of an Outlook user profile to easily implement it in new Outlook installation on additional or new devices. That way, a user profile does not have to be set up anew but can easily be imported using a PRF file.
Technical details of PRF files
The PRF file format contains all kinds of information Microsoft Outlook needs to create and update a user profile; such as e-mail signatures and folders, account settings, references and more. The information is saved in a plain text format using a syntax that can be interpreted by Outlook. When importing a PRF file in Outlook, the settings of an existing user profile are automatically updated.