I\'m getting this error:
tests.IntegrationTests.Selenium.RegisterAndLogin (TestFixtureSetUp): SetUp : OpenQA.Selenium.WebDriverException : Failed to start up
For anyone finding this question more recently (2015-02-27), there seems to be an open issue with compatibility with Selenium and Firefox 36:
https://code.google.com/p/selenium/issues/detail?id=8399
You can download Firefox 35 here: http://www.filehippo.com/download_firefox/59889/