In the first article called “How SSD Drives Permanently Erase Deleted Data” we described the reasons for SSD drives to erase your data permanently as soon as you erase a file, quick-format the disk or delete a partition. Sounds scary, doesn’t it? However, this is not always the case. More often than not, your files will still be there on the SSD drive, ready to be recovered. Let’s see when this happens.
TRIM: Not Always Working
TRIM is a great thing to optimize performance and longevity of an SSD drive. Without TRIM, you would get much slower write speeds and much faster wear of flash cells, which have a limited number of write cycles before failing.
However, in some situations TRIM does not engage. In particular, TRIM will not work if any of the following is true:
- You used an SSD drive in a USB enclosure. TRIM does not work over USB. (However, it does work over eSATA).
- You used one or more SSD drives in a NAS enclosure. (Most NAS units do not support TRIM, with the exception of some Synology units coupled with latest OS).
- You used two or more SSD drives in an internal RAID array. (Until recently, Windows did not support TRIM on RAID arrays. Even today, TRIM and RAID may not work together).
- You use Windows XP or Vista. (TRIM was added to Windows 7 and newer, including Windows 8 and 8.1) .
- Your SSD drive is formatted with FAT, FAT32 or exFAT. (In Windows, TRIM only works with NTFS).
- The disk or the file system is corrupted. (TRIM is only issued if you explicitly delete a file, format or repartition the disk. Otherwise, even if you don’t see any data and the disk appears empty or inaccessible, the TRIM command is not issued until you do the formatting or repartitioning).
- Non-Apple SSD on a Mac. (In Mac OS X, TRIM is only supported for Apple-supplied SSD drives).
If any of the following applies to you, go ahead and use a data recovery tool such as RS Partition Recovery – the chance that your data is still there is as high as with a traditional hard drive!