Using selenium for ui tests on our project. We are running the newest version 2.30.0.
We use Firefox WebDriver and are running Firefox 19.0.

Generally said the ui test works local and even server side when I run the ui test in Visual Studio. Our ui tests gets executed nighlty on our build server. It uses the same deploy on the same server I test manually via Visual Studio.

But sporadically we run into following issue when the ui test gets executed on buildserver: 

```
Test(s) failed. OpenQA.Selenium.WebDriverException : The HTTP request to the remote WebDriver server for URL http://localhost:7056/hub/session/bed1d0e7-efdc-46b6-ba07-34903519c44d/element/%7B8717bb19-96c7-44d3-b0ee-d4b989ae652d%7D/click timed out after 60 seconds.
      ----> System.Net.WebException : The operation has timed out
       at OpenQA.Selenium.Remote.HttpCommandExecutor.CreateResponse(WebRequest request)
       at OpenQA.Selenium.Remote.RemoteWebDriver.Execute(String driverCommandToExecute, Dictionary`2 parameters)
--WebException
   at System.Net.HttpWebRequest.GetResponse()
   at OpenQA.Selenium.Remote.HttpCommandExecutor.CreateResponse(WebRequest request)

```

Basically the test clicks on an upload button where the input field was filled with a file before. Since the file is very small this gets done in a few seconds.
Nevertheless the timout of 60 seconds is reached sometimes.

Any ideas how to isolate the underlying issue? Or run anybody into the same issue before?
Any hints appreciated. Thanks.