Decryption failed: Ciphertext too small

This error relates to the encryption of a Storage Vault (often a local Vault). The best resolution to this error is creating a new local Vault and pointing the backup to the new Vault. Additional details are discussed below.

This error is usually accompanied by the following text:

• Loading indexes: Retried 1 times over 9:20: Retried 10 times over 9:20: Load(<index/xxxxxxxx>): Decryption failed: Ciphertext too small
• The backup engine encountered a problem: exit status 1

The truncation of the ciphertext has numerous possible causes:

• Manual modification or deletion of Vault files
• Sharing the same local Vault between multiple user accounts (ex. User A and User B both push data to a folder called "Backup-Vault" on the same NAS)
• Lack of (or a minimal amount of) free space on the storage medium

Unfortunately, once the ciphertext becomes malformed, it is near-impossible to revert it to a workable state. One can attempt to run a manual retention pass to try and fix the Vault, though this effort should not be taken with the expectation of a resolution.

The current recommended resolution is creating a new Vault (see Creating a Storage Vault). Note: if the Vault is locally stored, ensure that the replacement Vault is completely new and that hidden files (such as those that start with a period) within the Vault are not retained.