Is TrueCrypt robust against data corruption?

I would expect a TrueCrypt volume to be fragile when it suffers from data corruption. This could happen for example because the hard disk, CD or DVD start to deteriorate, or when an USB stick is unplugged while a write is in progress.

In the TrueCrypt FAQ it is mentioned that this problem is limited because the data is encrypted in blocks of 16 bytes. However, I'd like to know if this really so in practice. Is there anyone who has experienced severe data loss due to only small corruptions?

Encrypted backups do have their drawbacks. In case the backup media becomes corrupted, you may lose everything whereas chances are much better to retrieve unencrypted backups (at least partially) from a damaged disk.

In any case, only one set of backups is insufficient. And if applicable, maintain an unencrypted backup in a safe location (e.g. a bank vault). Security comes at a price.

• For removable devices refer to this question
• Backups and redundancy (the RAID kind) are important
  • For optical media, move the data to new media every few years
    alternatively, stop using optical media and shift to newer forms of backup
    (yes, that too is your question)
• If you do hit a corruption later, check the recovery methods for your media
  Look at the next point in TrueCrypt FAQ,
  What do I do when the encrypted filesystem on my TrueCrypt volume is corrupted?

File system within a TrueCrypt volume may become corrupted in the same way as any normal unencrypted file system. When that happens, you can use filesystem repair tools supplied with your operating system to fix it. In Windows, it is the 'chkdsk' tool. TrueCrypt provides an easy way to use this tool on a TrueCrypt volume: Right-click the mounted volume in the main TrueCrypt window (in the drive list) and from the context menu select 'Repair Filesystem'.

I've lost 500 GB of data that was device encrypted. I tried everything; CHKDSK is useless when you can't mount the disk.

I lost 300 GB of data due to my volume header becoming corrupted by Windows. I had my entire system encrypted (boot partition and drives) and attempted to use the various repair features and decryption to no avail.

I would recommend only creating a TruCrypted partition and storing data there that you wouldn't mind losing for the benefit of the security it provides.