Selenium WebDriver throws Timeout exceptions sporadically

I got this same error: .NET WebDriver: 2.37, FF: 25.0.1. I noticed that Firefox was locking up until I exited my test application, so I built the debug version of Firefox and found that the lock-up happened when it was writing to stderr. This gave me the clue to change the webdriver code so that it no longer redirects standard out and error and this solved my problem. It seems like the WebDriver is blocking the std error in some way. From MSDN:

Synchronous read operations introduce a dependency between the caller reading from the StandardError stream and the child process writing to that stream. These dependencies can cause deadlock conditions...

More info here.

For anyone wanting to make the same tweak I did: -

1. Get the Selenium source. Then check out the same code branch that you are using.

2. In FireFoxBinary.cs:

   i. Wherever you find RedirectStandardError = true, change to RedirectStandardError = false.

   ii. Wherever you find RedirectStandardOutput = true, change to RedirectStandardOutput = false. (for non-Windows, there is also one in Executable.cs)

   iii. In ConsoleOuput, change 'return this.stream.ReadToEnd()', to 'return ""'

3. Build and replace WebDriver.dll with yours.

Disclaimer: This worked for me, but your issue might be different. Also as far as I can tell, this has no adverse effects other than disabling the console output, but there may be other side effects that I am unaware of.

I would be interested to know if anyone else finds the same.

Since I have solved my problem, I will not dig any deeper. If anyone a Selenium group member wants more info / logs / tweaks I would be happy to do so.

Hopefully this will get fixed soon.

Update

It appears that Firefox v25 is not currently supported. See this comment.

Update 25th Feb 2014

See this update:

Okay, this issue in general does not manifest itself in IE, or so it seems from the comments. I'd like people to try with Firefox and Chrome, and the .NET bindings 2.40.0 (will be the next release at the time of this writing) or later, and see if this is still happening.

I've seen fewer reports of this happening in Chrome since 2.35.0, so I need to know if this is still an issue with the .NET bindings and a recent chromedriver.exe.

2.40.0 may have a fix for at least one of the issues that may cause this in Firefox.

This solved the problem for me. Looking at the change log, there is a commit from 1/31/2014 to remove console logging redirection:

"No longer redirecting console output for Firefox in .NET bindings."

Which is the workaround I used here. So, it all makes sense.

Happened to me in four different scenarios:

1. The cause was that the window handle I was querying was already closed or in closing stages.If this is the case, you better check that the window still exist before querying it.If you want to avoid the long timeout period of 60 seconds, you should change the way you create the Firefox instance to decrease the 60 seconds delay:

   new FirefoxDriver("FfBinaryPath", FfProfileInstance, TimeSpan.FromSeconds(5));

2. The cause was the flash plugin 'Protected Mode'.This scenario happened to me only under windows 7 and 8 when they ran under Jenkins job, the timeout did not happened sporadically.In order to fix it, I ran my Firefox selenium instance with the flash security mode disabled:

   FfProfile.SetPreference("dom.ipc.plugins.flash.disable-protected-mode", true);

3. Another cause, also non sporadic, under Jenkins and related to Flash, happened when using Firefox version 45. In order to resolve this issue I had to downgrade to version 44 or alteratively uninstall Flash.

4. Internal browser reason: Sometimes the browser takes more than one minute to react Selenium calls. In such case, setting the browser command timeout above 60 seconds can solve the issue. for example:

   new FirefoxDriver("FfBinaryPath", FfProfileInstance, TimeSpan.FromMinutes(3));

I had the same error with timing out. I was using the IEDriverServer (64bit) and on long sendKey commands it would timeout.

The reason being is that the default timeout seems to be 60 seconds.

What fixed my issue is that I instantiated the driver with a method that enables you to enter in the location of the IEDriverServer, the options for the driver AND the timeout value.

Link to documentation : http://seleniumhq.github.io/selenium/docs/api/dotnet/

public InternetExplorerDriver(    string internetExplorerDriverServerDirectory,    InternetExplorerOptions options,    TimeSpan commandTimeout)

Parameters

1. InternetExplorerDriverServerDirectory:
   • Type : System.String
   • The full path to the directory containing IEDriverServer.exe
2. options
   • Type : OpenQA.Selenium.IE.InternetExplorerOptions
   • The InternetExplorerOptions used to initialize the driver
3. commandTimeout
   • Type : System.TimeSpan
   • The maximum amount of time to wait for each command

My code

InternetExplorerOptions options = new InternetExplorerOptions();        IWebDriver driver = new InternetExplorerDriver("C:/Users/jeff/AppData/Local/Microsoft/WindowsApps", options, TimeSpan.FromSeconds(120));