when you deleted files by accident or when your sd card shows raw file system, not formatted card errors... or you simply formatted sd card by error. You can recover deleted files off sd card
with Asoftech data recovery
software. Download from: SD card files undelete tutorial
Features of Asoftech Data Recovery
1. Recover files lost for almost all reasons, as long as the card is not physically damaged. No matter they are lost due to mistaken deletion, format, or power surge, virus attack, etc.
2. Recover files on not only SD card, but all other storage media such as external hard disk, flash drive and hard disks.
3. Allow you to preview the found files before you do the recovery.
4. Slimmed-down interface, easy to understand and use.
5. Perform read-only data recovery, without altering or adding any data on the target partition.
Some other data recovery solution:
Recover deleted photos from SD card for free
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Samsung EVO SD card recovery solution