walletpassphrasechange "oldpassphrase" "newpassphrase"
Changes the wallet passphrase from 'oldpassphrase' to 'newpassphrase'.
Arguments:
1. oldpassphrase (string, required) The current passphrase
2. newpassphrase (string, required) The new passphrase
Result:
null (json null)
Examples:
> bitcoin-cli walletpassphrasechange "old one" "new one"
> curl --user myusername --data-binary '{"jsonrpc": "1.0", "id": "curltest", "method": "walletpassphrasechange", "params": ["old one", "new one"]}' -H 'content-type: text/plain;' http://127.0.0.1:8332/