File Extension Unknown doesn't belong to any specific application. Existence of these files typically indicates problems with Windows Registry or presence of malware.

Windows registry is integrated in current Windows operating systems to restore the older INI files which also enclosed system configuration. Windows registry also includes settings for the hardware, software, and users. Each time a new application is installed or an administrator alters some settings from the Control Panel, matching changes with the settings of the computer’s preferences are made to the registry.

Because of the attractiveness of Windows operating systems, many computer fanatics are testing several ways to hack the systems. The registry is one of the great target by these attackers because it encloses all configurations needed for the computer to function normally.

If you encounter File Extension Unknown error, try to download for free the Driver Detective to update your registry instantly and make your PC running error-free.