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Migration store encryption

This article discusses User State Migration Tool (USMT) options for migration store encryption to protect the integrity of user data during a migration.

USMT encryption options

USMT enables support for stronger encryption algorithms, called Advanced Encryption Standard (AES), in several bit-level options. AES is a National Institute of Standards and Technology (NIST) specification for the encryption of electronic data.

The chosen encryption algorithm must be specified for both the ScanState.exe and the LoadState.exe commands, so that these commands can create or read the store during encryption and decryption. The new encryption algorithms can be specified on the ScanState.exe and the LoadState.exe command lines by using the /encrypt:encryption_strength and the /decrypt:encryption_strength command-line options. All of the encryption application programming interfaces (APIs) used by USMT are available in currently supported versions of Windows. However, export restrictions might limit the set of algorithms that are available to computers in certain locales. The UsmtUtils.exe file can be used to determine which encryption algorithms are available to the computers' locales before the migration begins.

The following table describes the command-line encryption options in USMT.

Component Option Description
ScanState /encrypt<AES, AES_128, AES_192, AES_256, 3DES, 3DES_112> This option and argument specify that the migration store is encrypted and which algorithm to use. When the algorithm argument isn't provided, the ScanState tool employs the 3DES algorithm.
LoadState /decrypt<AES, AES_128, AES_192, AES_256, 3DES, 3DES_112> This option and argument specify that the store must be decrypted and which algorithm to use. When the algorithm argument isn't provided, the LoadState tool employs the 3DES algorithm.

Important

Some encryption algorithms might not be available on some systems. Which algorithms are available can be verified by running the UsmtUtils.exe command with the /ec option. For more information, see UsmtUtils syntax.