I'm new to ethereum and blockchain technology. I'm trying to create my own crypto currency and using below JSON-RPC for creating new contract in our ethereum wallet on test network.

curl http://**.**.**.***:8545 -X POST --data '{"jsonrpc":"2.0","method":"eth_sendTransaction","params":[{"from": "0xcfd3db0f1a6cb6cbbaf2b46f773444c3f13e1fe3", "data": "0x606060405260728060106000396000f360606040526000357c0100000000000000000000000000000000000000000000000000000000900480636ffa1caa146037576035565b005b604b60048080359060200190919050506061565b6040518082815260200191505060405180910390f35b6000816002029050606d565b91905056"}],"id":1}'

after using this command I'm recieving following error

{"jsonrpc":"2.0","id":1,"error":{"code":-32000,"message":"authentication needed: password or unlock"}}

I am confused what I am missing here, any help would be highly appreciated.


You need to unlock your accout with your password in order to be able to send a transaction. In the console you should type:

personal.unlockAccount(address, "password")

After successfully unlocking your account, you will be able to send transactions from the unlocked account! Good luck!

  • still getting the same response {"jsonrpc":"2.0","id":1,"error":{"code":-32000,"message":"authentication needed: password or unlock"}} – Rahul Sati Oct 3 '17 at 8:03
  • Hmm...are you sure that you unlock the very same account from which you actually want to deploy the contract? – István András Seres Oct 3 '17 at 8:07
  • Done, for making successfull transaction I have addded the "gas" and "gasPrice" to the RPC call { curl http://**.**.**.***:8545 -X POST --data '{"jsonrpc":"2.0","method":"personal_sendTransaction","params":[{"from": "0xcfd3db0f1a6c********************", "data":"complied code", "gas" : "0x76c00", "gasPrice" : "0x9184e72a000"},"password"],"id":1}' } – Rahul Sati Oct 3 '17 at 10:15

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