Facing error when running grunt server

[CrashLaker]

Hi all,

Just tried compiling this and got the following error:

(node:28467) UnhandledPromiseRejectionWarning: Error: Exited with code 3
  at ChildProcess.<anonymous> (/root/github/winstrap/node_modules/opn/index.js:83:13)
  at Object.onceWrapper (events.js:286:20)
  at ChildProcess.emit (events.js:198:13)
  at maybeClose (internal/child_process.js:982:16)
  at Socket.stream.socket.on (internal/child_process.js:389:11)
  at Socket.emit (events.js:198:13)
  at Pipe._handle.close (net.js:606:12)

(node:28467) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:28467) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

I'm using node 10.16.3
node 6.*

Can anyone help me?

thanks

[CrashLaker]

Just realized I'm actually able to access the website..