`oz call` Cannot read property 'message' of null

Hi all,

I'm getting an error message when using the SDK

npx oz call
? Pick a network rinkeby
Cannot read property 'message' of null

Any idea?


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Hi @CIX,

Is rinkeby network setup ok (feel free to share your setup)?
You could try npx oz accounts to check the setup.

Please note: We’ve decided it’s best to focus our upgradeability efforts on the Upgrades Plugins exclusively, and have halted development on the OpenZeppelin CLI. We will continue to provide support for the CLI until the end of 2020.
See: Building for interoperability: why we’re focusing on Upgrades Plugins

Hi @abcoathup,

npx oz accounts gives me the same message! The setup seems ok to me… maybe the HDWalletProvider?

ropsten: {
        provider: () => new HDWalletProvider(process.env.DEV_ROPSTEN, `wss://ropsten.infura.io/ws/v3/${process.env.INFURA_API}`),
        network_id: 3,
        websockets: true

  "contracts": {},
  "solidityLibs": {},
  "proxies": {
    "@openzeppelin/contracts-ethereum-package/ERC20PresetMinterPauserUpgradeSafe": [
        "address": "0x747B04a0d3DF924eC71BB149B667BcDa7c1dEe4F",
        "version": "3.0.0",
        "implementation": "0xb1938665526857e08E488E6713B8Bdf8D15e8928",
        "admin": "0x991D5A711fF4Bf2420Eb28EA0aaF6c8Ef750F3F7",
        "kind": "Upgradeable"
  "manifestVersion": "2.2",
  "version": "1.0.0",
  "dependencies": {
    "@openzeppelin/contracts-ethereum-package": {
      "package": "0x2a9e7B63514438906A83a1e320dBBD814D417002",
      "version": "3.0.0"
  "proxyAdmin": {
    "address": "0x991D5A711fF4Bf2420Eb28EA0aaF6c8Ef750F3F7"
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seems the problem was node/npm! Hopefully, it will help someone

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Hi @CIX,

What did you do to resolve the node/npm issue?

I recommend migrating to OpenZeppelin Upgrades Plugins, either using Truffle or Hardhat.

I simply uninstall Node via nvm and reinstall…

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