The moment you realize data is missing, stop using the computer. Every new file saved (even temporary internet files) could overwrite your lost data.
If the drive is making clicking noises or has physical damage, software cannot fix it. You will need a professional data recovery service Are you trying to recover data from an (like Windows XP) or a modern device Easyrecovery Professional 6.03 Full
If you are looking for , it is a legacy version of the popular data recovery software originally developed by Ontrack (now often referred to as Kroll Ontrack). The moment you realize data is missing, stop