To encrypt backups I prefer to store them on BitLocker encrypted drives.
If you are starting backup using hook „When USB disk connected“ to BitLocker enabled drive you will be getting error that drive is encrypted and backup cannot proceed.
To solve it, enable automatic unlocking of the drive using this powershell command:
Enable-BitlockerAutoUnlock -MountPoint "X:"
This will enable unlocking for all accounts on that computer from which you will run this command.