Deploy to ropsten

[laitassou]

Hi, I would deploy the box to ropsten. the code works fine in localhost but I got his error in ropsten:

The contract is deployed but impossible to connect to via js code

vRtx5LtC6D1enY0g6x0k:1 POST https://ropsten.infura.io/xxxxxxx
main.js:36 Error: Invalid JSON RPC response: ""
at Object.InvalidResponse (inpage.js:1)
at XMLHttpRequest.r.onreadystatechange (inpage.js:1)

Here is the begeninng of login function :

let web3 = new Web3(new Web3.providers.HttpProvider("https://ropsten.infura.io/vRtx5LtC6D1enY0g6x0k"));

/////let web3 = store.getState().web3.web3Instance
web3.eth.defaultAccount = web3.eth.accounts[0];

// Double-check web3's status.
if (typeof web3 !== 'undefined') {

  // Using truffle-contract we create the authentication object.
  const authentication = contract(AuthenticationContract)

  /////const authentication =  web3.eth.contract(AuthenticationContract,'0x3661a5a703696eb2702f9feba51da416e97a39a2')