protractor: Cannot launch Chrome: OSX 10.9.3, Selenium 2.42.0, chromedriver 2.10

Trying to run protractor tests on OSX. We get the error below. Have tried a variety of fixes suggested. I think we’re running the latest stand-alone server and chrome driver. Thoughts?

/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/atoms/error.js:109
 var template = new Error(this.message);
                ^
UnknownError: null
   at new bot.Error (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/atoms/error.js:109:18)
   at Object.bot.response.checkResponse (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/atoms/response.js:106:9)
   at /Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/webdriver/webdriver.js:134:24
   at /Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/goog/base.js:1243:15
   at webdriver.promise.ControlFlow.runInNewFrame_ (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/webdriver/promise.js:1531:20)
   at notify (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/webdriver/promise.js:354:12)
   at notifyAll (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/webdriver/promise.js:323:7)
   at resolve (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/webdriver/promise.js:301:7)
   at fulfill (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/webdriver/promise.js:421:5)
   at /Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/goog/base.js:1243:15
==== async task ====
WebDriver.createSession()
   at Function.webdriver.WebDriver.acquireSession_ (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/webdriver/webdriver.js:131:49)
   at Function.webdriver.WebDriver.createSession (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/lib/webdriver/webdriver.js:111:30)
   at Builder.build (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/selenium-webdriver/builder.js:106:20)
   at HostedDriverProvider.getDriver (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/lib/driverProviders/hosted.js:54:9)
   at /Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/lib/runner.js:207:35
   at _fulfilled (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/q/q.js:797:54)
   at self.promiseDispatch.done (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/q/q.js:826:30)
   at Promise.promise.promiseDispatch (/Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/q/q.js:759:13)
   at /Users/riley/dash.frontend/node_modules/grunt-protractor-runner/node_modules/protractor/node_modules/q/q.js:525:49