IfyourPCopenstheRDDfile,butit'sthewrongapplication,you'llneedtochangeyourWindowsregistryfileassociationsettings.Inotherwords,WindowsisassociatingRDDfileextensionswiththewrongsoftwareprogram.

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If your PC opens the RDD file, but it's the wrong application, you'll need to change your Windows registry file association settings. In other words, Windows is associating RDD file extensions with the wrong software program.