C# – Selenium Error – The HTTP request to the remote WebDriver timed out after 60 seconds

I've been using Selenium for a number of months, which we're using to automate some of our internal testing processes. The scripts have been passing fine. I've recently upgraded to C# 2.40.0 webdriver using FF 27.01 and our scripts are now failing in random places with the following error.

[Portal.SmokeTest.SmokeRunTest.Booking] TearDown method failed. OpenQA.Selenium.WebDriverException : The HTTP request to the remote WebDriver server for URL htt(p)://localhost:7055/hub/session/56e99e88-ba17-4d12-bef1-c6a6367ccc2f/element timed out after 60 seconds.
  ----> System.Net.WebException : The operation has timed out
TearDown : OpenQA.Selenium.WebDriverException : The HTTP request to the remote WebDriver server for URL htt(p)://localhost:7055/hub/session/56e99e88-ba17-4d12-bef1-c6a6367ccc2f/window timed out after 60 seconds.
  ----> System.Net.WebException : The operation has timed out
[09:01:20]
[Portal.SmokeTest.SmokeRunTest.Booking] TearDown method failed. OpenQA.Selenium.WebDriverException : The HTTP request to the remote WebDriver server for URL htt(p)://localhost:7055/hub/session/56e99e88-ba17-4d12-bef1-c6a6367ccc2f/element timed out after 60 seconds.
  ----> System.Net.WebException : The operation has timed out
TearDown : OpenQA.Selenium.WebDriverException : The HTTP request to the remote WebDriver server for URL htt(p)://localhost:7055/hub/session/56e99e88-ba17-4d12-bef1-c6a6367ccc2f/window timed out after 60 seconds.
  ----> System.Net.WebException : The operation has timed out
   at OpenQA.Selenium.Support.UI.DefaultWait`1.PropagateExceptionIfNotIgnored(Exception e)
   at OpenQA.Selenium.Support.UI.DefaultWait`1.Until[TResult](Func`2 condition)
   at Portal.Test.Helpers.Process_Bookings.OpenBookings.SelectBooking(String bookingnumber)
   at Portal.SmokeTest.SmokeRunTest.Booking() in d:\TeamCityAgent\work\dac1dcea7f2e80df\SmokeTests\SmokeRunTest.cs:line 68
--WebException
   at System.Net.HttpWebRequest.GetResponse()
   at OpenQA.Selenium.Remote.HttpCommandExecutor.CreateResponse(WebRequest request)
--TearDown
   at OpenQA.Selenium.Remote.HttpCommandExecutor.CreateResponse(WebRequest request)
   at OpenQA.Selenium.Remote.HttpCommandExecutor.Execute(Command commandToExecute)
   at OpenQA.Selenium.Firefox.Internal.ExtensionConnection.Execute(Command commandToExecute)
   at OpenQA.Selenium.Remote.RemoteWebDriver.Execute(String driverCommandToExecute, Dictionary`2 parameters)
   at OpenQA.Selenium.Remote.RemoteWebDriver.Close()
   at Portal.Test.Helpers.Setup.CloseWebdriver()
   at Portal.SmokeTest.SmokeRunTest.TearDown() in d:\TeamCityAgent\work\dac1dcea7f2e80df\SmokeTests\SmokeRunTest.cs:line 162
--WebException
   at System.Net.HttpWebRequest.GetResponse()
   at OpenQA.Selenium.Remote.HttpCommandExecutor.CreateResponse(WebRequest request)

The latest error I've managed to track down to one single line of code:

_setup.driver.FindElement(By.XPath("//button[@class='buttonSmall lockBookingButton']")).Click();

The annoying thing is, trying to fix the problem is proving difficult, as if I run the test on my local machine, in debug it passes. Additionally, if I run it via the NUNIT runner on the build machine I'm running the test off, it also passes. It only seems to fail as part of our automated build running process when using Teamcity. Like I said, this has been running fine for months previously, and the only thing that has changed is the selenium webdriver kit.

I have experienced this problem before, whilst in debug, and when a Click() line of code was called, Firefox appeared to lock up, and only stopping the test would allow Firefox to continue. There are a number of suggestions on here including modifying the webdriver source? I'd like to not go down that route if possible if anyone else can offer any suggestions.