Due to hardware or software errors/malfunctions, files stored on a TrueCrypt volume may become corrupted. Therefore, we strongly recommend that you backup all your important files regularly (this, of course, applies to any important data, not just to encrypted data stored on TrueCrypt volumes).

If you do not have enough free space to backup all files, we highly recommend that you at least backup the volume header, which contains the master key (size of the backup file will be 1024 bytes). If a volume header is damaged, the volume is, in most cases, impossible to mount.

For more information, please see the chapter Backing Up Volumes and Volume Headers.

Important: Several users reported that data on their TrueCrypt volumes were becoming corrupted. Later, these users found out that it was not a problem with TrueCrypt but with their hardware (chipset, USB hard drive, cables, USB PCI card, etc.) Therefore, we recommend that you make sure data written to the unencrypted device (where you intend to create a TrueCrypt volume) is not becoming corrupted. For example, by copying a large set of files (at least several gigabytes in total) and then comparing the original files with the copies (by content) using e.g. the command line tool fc supplied with Windows.