Whether you're using a digital camera, smartphone or MP3 player, you probably have a lot of important data saved on the device's Secure Digital (SD) card. This data may get compromised if you insert your SD card into another device. The new device may reformat the card, potentially resulting in data loss. If this happens, you may need to unformat the SD card to retrieve your data. The good news is, there's a way to unformat an SD card yourself--all it takes is a freeware (free software) program and a little time.
Open your Internet browser, and navigate to the home page of a data recovery freeware site (see the links in the Resource section). Download the program you select. The only way to unformat your SD card yourself is to use one of these free data recovery programs.
Insert your SD card into the appropriate slot on your computer. For PCs, the SD card slot is located near the disc tray. If you're using a MAC, insert your SD card into its appropriate device (digital camera, MP3 player), and plug the device into the computer via the USB port on your Mac.
Open the freeware program you recently downloaded by clicking on its icon on the desktop of your computer.
Select "Mac" or "PC" from the main menu of the program.
Select "Data Recovery" from the list of function options. The program begins the process of unformatting the formatted SD card to recover any lost data on the card.
Wait for the computer program to finish unformatting the card and locating data. You'll know when it's finished when the status bar on the program screen is complete. Afterward, any lost data displays in a window in the program, and your micro SD card is unformatted.