DecryptFile
DecryptFile["password", file] generates a decrypted version of a file, using the specified password.
DecryptFile["password", source, target] generates a decrypted version of source, putting the result in target.
DecryptFile[keyspec, source, ...] decrypts using the cryptographic key specification keyspec.
Examples
Decrypt a file:
DecryptFile["mypassword", "encrypted.dat", "decrypted.dat"]Please visit the official Wolfram Language Reference for more details.