There is free app called Recuva (https://www.piriform.com/recuva)
Recuva works on just about any rewriteable media you might have. Whether you need to recover precious photographs out of your digital camera’s memory card, files you backed up to an external harddrive, or your documents you take with you every day on your USB key, Recuva’s received you included. For prosumer and also pro photographers, Recuva helps the Nikon RAW and Canon RAW (. CRW) formats.file.
Recuva is absolutely a free data recovery tool, which can help you recover documents deleted by mistake, or immediately after virus attacks and system crashes. It works not only with hard disks, but having removable devices too, in addition to with cameras, iPods, and mp3 players.
Once you have installed Recuva on your system, the Recuva Wizard will automaticily start.