- The RPC
createwalletnow has an optionalblankargument that can be used to create a blank wallet. Blank wallets do not have any keys or HD seed. They cannot be opened in software older than 0.18. Once a blank wallet has a HD seed set (by usingsethdseed) or private keys, scripts, addresses, and other watch only things have been imported, the wallet is no longer blank and can be opened in 0.17.x. Encrypting a blank wallet will also set a HD seed for it.