TestDisk was primarily designed to help recover lost partitions and/or make non-booting disks bootable again when these symptoms are caused by faulty software, certain types of viruses or human error (such as accidentally erasing your Partition Table).

TestDisk is a free and useful program which queries the BIOS ( DOS/Win9x) or the OS ( Linux, FreeBSD) in order to find the Hard Disks and their characteristics ( LBA size and CHS geometry). TestDisk does a quick check of your disk's structure and compares it with your Partition Table for entry errors.

If the Partition Table has entry errors, TestDisk can repair them. If you have missing partitions or a completely empty Partition Table, TestDisk can search for partitions and create a new Table or even a new MBR if necessary.

However, it's up to the user to look over the list of possible partitions found by TestDisk and to select the one(s) which were being used just before the drive failed to boot or the partition(s) were lost. In some cases, especially after initiating a detailed search for lost partitions, TestDisk may show partition data which is simply from the remnants of a partition that had been deleted and overwritten long ago.

TestDisk has features for both novices and experts. For those who know little or nothing about data recovery techniques, the command line parameters /log and /debug can be used to collect detailed information about a non-booting drive which can then be sent to a tech for further analysis. Those more familiar with such procedures should find TestDisk a handy tool in performing onsite recovery.

TestDisk can find lost partitions for all of these file systems:
· BeFS ( BeOS )
· BSD disklabel ( FreeBSD/OpenBSD/NetBSD )
· CramFS, Compressed File System
· DOS/Windows FAT12, FAT16 and FAT32
· HFS and HFS+, Hierarchical File System
· JFS, IBM's Journaled File System
· Linux Ext2 and Ext3
· Linux Raid
· RAID 1: mirroring
· RAID 4: striped array with parity device
· RAID 5: striped array with distributed parity information
· RAID 6: striped array with distributed dual redundancy information
· Linux Swap (versions 1 and 2)
· LVM and LVM2, Linux Logical Volume Manager
· Mac partition map
· Novell Storage Services NSS
· NTFS ( Windows NT/2K/XP/2003 )
· ReiserFS 3.5, 3.6 and 4
· Sun Solaris i386 disklabel
· Unix File System UFS and UFS2 (Sun/BSD/...)
· XFS, SGI's Journaled File System

What's New in This Release: [ read full changelog ]

General Improvements:
· Fix UAC manifests for Windows, so users don't need to use right-click "Run As Administrator"

TestDisk:
· Fix image creation, image.dd file wasn't created (Regression introduced in 6.12)
· Detect Vmware VMFS partition
· Locate lost GFS2 partition but not yet the size
· Log HDD serial number and firmware revision
· List NTFS Alternate Data Streams (ADS)

PhotoRec:
· Session recovery restarts at the previous location
· Better MPEG recovery, there should be less concatenated videos.
· Better JPG recovery, there should be less cases where thumbnails were recovered instead of the picture itself.
· Handle large avi files using "AVIX" or mov files using 64-bit chunk size.
· Rename recovered pdf using the title (not perfect)
· Major cleanup of PhotoRec core code
New file formats:
· caf Core Audio Format
· dardar3 archive
· ddf Didson Data File (v3 and v4)
· gcs GCstart (personal collections manager)
· gam Games Factory
· hdf Hierarchical Data Format 4
· hdr ENVI
· max 3ds
· oci OpenC...