Memory cards, USB Drives and even SSDs are small, hold a good amount of data and don’t have all those pesky data corruption issues that traditional hard drives have… Or do they?
Yes, even data on a flash media can get corrupted or at the very least, accidentally erased. If this has happened to you, I’ll show you what you can do – assuming the media itself isn’t damaged, crushed, or physically destroyed in any way.
While it’s rare for memory cards to get corrupted, it happens. Once I had a defective USB drive that corrupted everything I put on it, even the first time I used it. More likely to happen though, is an accidental erase. With a confusing menu system on digital cameras, or someone maliciously erasing photos, it can happen often.
Step One: Remove the Card.
If something does get accidentally erased or corrupted, the first thing you should do is remove the memory card from the camera, cell phone or whatever device. You do not want to overwrite new data on top of the accidentally erased data. Doing so would make recovery next to impossible.
Step Two: Find a Card Reader.
In order for your Mac to directly read Compact Flash, Memory Stick, SD Cards or any other non-USB media, you’ll need a Card Reader. You can purchase one if you think you’ll need it – Here’s a recommended one from Kingston.
Don’t have a card reader? If it’s a Micro SD card, you can use an mp3 player such as the SanDisk Sansa Series with a Micro SD slot. You may also be able to use your digital camera as the reader if it mounts the memory card as an external drive in OS X.
Step Three: Using PhotoRec.
1. Download the incredible open source TestDisk and PhotoRec from CGSecurity.
2. PhotoRec runs in the Terminal – Don’t be intimidated.
3. UnArchive the download and open the “darwin” folder.
4. Start PhotoRec by double-clicking. Terminal will open up.
5. Select your disk. Go by size to determine which disk is which.
Note: In OS X, its recommended you chose the /dev/rdisk version, if available. It goes faster.
6. Choose your partition table. (PhotoRec will auto select it for you).
7. Select the Partition and choose “Search” at the bottom.
8. PhotoRec needs to know what filesystem your media was set up with.
Note: Unless you used EXT2 or EXT3, just choose other.
9. Select Free to scan only the free space (Recover Deleted Files only). Or choose Whole if the entire media is corrupted.
10. Select where you want to save the recovered files. Hit Y when ready.
11. PhotoRec will now work its magic!