How to fix Selenium WebDriverException: The browser appears to have exited before we could connect?

Question

I have installed firefox and Xvfb on my centos6.4 server to use selenium webdriver.

But, when I run the code, I got an error.

from selenium import webdriver
browser = webdriver.Firefox()

Error

selenium.common.exceptions.WebDriverException: Message: 
'The browser appears to have exited before we could connect. The output was: None'

I read some related pages on stackoverflow and someone suggested to remove all files in tmp folder, so I did it. But, it still doesn't work.

Could anyone please give me a help?

Thank you in advance!

Edit

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.4/site-packages/selenium/webdriver/firefox/webdriver.py", line 59, in __init__
    self.binary, timeout),
  File "/usr/local/lib/python3.4/site-packages/selenium/webdriver/firefox/extension_connection.py", line 47, in __init__
    self.binary.launch_browser(self.profile)
  File "/usr/local/lib/python3.4/site-packages/selenium/webdriver/firefox/firefox_binary.py", line 64, in launch_browser
    self._wait_until_connectable()
  File "/usr/local/lib/python3.4/site-packages/selenium/webdriver/firefox/firefox_binary.py", line 103, in _wait_until_connectable
    self._get_firefox_output())
selenium.common.exceptions.WebDriverException: Message: 'The browser appears to have exited     before we could connect. The output was: None'

I have installed selenium via pip command. It is "Version: 2.43.0" — W3Q, Sep 27 '14 at 03:50
One option: you can output `pip freeze` and see what is there for `selenium`. — alecxe, Sep 27 '14 at 03:50
Also, what if you try chrome? `browser = webdriver.Chrome()`? — alecxe, Sep 27 '14 at 03:51
Thanks for your help. I found out that selenium's version is 2.43.0. — W3Q, Sep 27 '14 at 03:52
When I run "webdriver.Chrome()", I got this error. "selenium.common.exceptions.WebDriverException: Message: 'ChromeDriver executable needs to be available in the path." I haven't installed "chrome" onto my server. — W3Q, Sep 27 '14 at 03:53
Hey, any progress with the issue? Did you have any success with chrome? — alecxe, Sep 27 '14 at 19:00
I have installed Google Chrome, but it's not working.When I run "webdriver.Chrome(executable_path="/usr/bin/google-chrome")", I get this error."selenium.common.exceptions.WebDriverException: Message: 'Can not connect to the ChromeDriver' " — W3Q, Sep 28 '14 at 01:30
I'm not sure if this is causing this error. when I run $ google-chrome , I get this error "google-chrome: /usr/lib64/libstdc++.so.6: version `GLIBCXX_3.4.15' not found (required by google-chrome)" — W3Q, Sep 28 '14 at 01:32
I've tried updating gcc but I got errors while compiling it. This is beyond my capacity, I guess... I've spent more than at least 10 hours for selenium webdriver but no outcome at all. I feel kinda depressed now :( — W3Q, Sep 28 '14 at 02:48
There was a known bug which supposedly was fixed: https://code.google.com/p/selenium/issues/detail?id=7823 However, I have the latest version of selenium and firefox but I also get the error you have here. I've double checked permissions on the python file as well as the /tmp directory which it writes logs too. Everything seems fine. I have no idea why it won't work. — melchoir55, Nov 15 '14 at 03:10

score 76 · Answer 1 · edited May 23 '17 at 11:46

for Googlers, this answer didn't work for me, and I had to use this answer instead. I am using AWS Ubuntu.

Basically, I needed to install Xvfb and then pyvirtualdisplay:

sudo apt-get install xvfb
sudo pip install pyvirtualdisplay

Once I had done that, this python code worked:

#!/usr/bin/env python

from pyvirtualdisplay import Display
from selenium import webdriver

display = Display(visible=0, size=(1024, 768))
display.start()

browser = webdriver.Firefox()
browser.get('http://www.ubuntu.com/')
print browser.page_source

browser.close()
display.stop()

Thanks to @That1Guy for the first answer

score 27 · Answer 2 · answered Jun 11 '16 at 04:53

I was running into this on an (headless) Ubuntu 14.04 server with Jenkins and xvfb installed. I had installed the latest stable Firefox (47) which started a build failing that ran a python script which used the Firefox driver for selenium (version 2.53).

Apparently Firefox 47+ is not compatible with the driver used in Selenium 2.53, and Selenium 3+ will be using a new driver called "Marionette" or "Gecko Driver" (which isn't officially released yet).

This page explains how to use the new driver pretty well, in several languages: https://developer.mozilla.org/en-US/docs/Mozilla/QA/Marionette/WebDriver

Basically:

get/build the executable from the project on github: https://github.com/mozilla/geckodriver/releases (and make sure it's perms are set to be executable, IE chmod a+x /path/to/geckdriver-executable)
rename/copy binary to "wires"
make sure the binary's location is added to the PATH that the build uses when executing the selenium test
update the selenium test to use the new driver

For Python, step 4 looked something like the following for me:

from selenium import webdriver
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities

firefox_capabilities = DesiredCapabilities.FIREFOX
firefox_capabilities['marionette'] = True
firefox_capabilities['binary'] = '/usr/bin/firefox'

driver = webdriver.Firefox(capabilities=firefox_capabilities)

If it was working for you in the past, and after a Firefox update you're now getting "WebDriverException: Message: The browser appears to have exited before we could connect.", this is probably the explanation. — medmunds, Jun 13 '16 at 23:04
Here's more info: https://github.com/SeleniumHQ/selenium/issues/2110#issuecomment-224413609. Alternatives to switching to Marionette right now are reverting to FF 46, or waiting for Mozilla to release a FF 47 patch that fixes this. — medmunds, Jun 13 '16 at 23:10
At step 3 I put the file at: `/usr/local/bin/wires`. Thanks! — Caumons, Jun 23 '16 at 09:56
Update: It appears that FF48 again create problems; neither the original webdriver.Firefox version or the version including marionette work (the second giving back "WebDriverException: Service wires unexpectedly exited. Status code was: 1") — Ando Jurai, Aug 08 '16 at 07:08

score 22 · Answer 3 · edited Jul 25 '16 at 16:03

22

I too had faced same problem. I was on Firefox 47 and Selenium 2.53; I downgraded Firefox to 45. This worked.

Remove Firefox 47 first :
```
sudo apt-get purge firefox
```
Check for available versions:
```
apt-cache show firefox | grep Version
```
It will show available firefox versions like:

Version: 47.0+build3-0ubuntu0.16.04.1
Version: 45.0.2+build1-0ubuntu1

Install a specific version

sudo apt-get install firefox=45.0.2+build1-0ubuntu1

Next you have to not upgrade to the newer version again.
```
sudo apt-mark hold firefox
```

If you want to upgrade later

sudo apt-mark unhold firefox
sudo apt-get upgrade

edited Jul 25 '16 at 16:03

Toby Speight

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answered Jul 09 '16 at 09:28

Amogh Joshi

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13

1

Thanks a million for this workaround. I was stuck with this problem for a while. – sudhishkr Jul 10 '16 at 00:25
1

@sudhishkr I know the frustration... Glad the solution helped. – Amogh Joshi Jul 11 '16 at 03:18
1

@AmoghJoshi is this a problem with selenium or Firefox? Has this been logged as bug with them? – user_3068807 Jul 26 '16 at 12:39
1

@Shafaq That's right its a problem with Selenium.It has been logged as a bug. Here's the link to change log : https://raw.githubusercontent.com/SeleniumHQ/selenium/master/py/CHANGES. You can see they have tried to solve compatibility issues with firefox web driver. – Amogh Joshi Jul 26 '16 at 13:08
Thanks bro, it's really useful with me – Duy Trần Aug 05 '16 at 02:51

score 11 · Answer 4 · edited Apr 24 '15 at 23:11

11

Check your DISPLAY environment variable. Run echo $DISPLAY in the command line.

If nothing is printed, then you are running FireFox without any DISPLAY assigned. You should assign one! Run export DISPLAY=:1 in the command line before running your python script.

Check this thread for more information: http://hashcat.net/forum/thread-1973.html

edited Apr 24 '15 at 23:11

burkemw3

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16

answered Jan 14 '15 at 07:32

Bilal Naqvi

140
1
11

Helpful tip: If you are running Ubuntu 14.04 in Headless mode, you likely want `export DISPLAY=:99`. This is what worked for me. – steve-gregory Dec 04 '15 at 14:49
1

Ran into this with Jenkins Xvfb plugin: its default config sets `DISPLAY=:0`, which is invalid. You need to override in job config > build environment > xvfb advanced: "Xvfb display name offset". Easy to track down with `echo $DISPLAY` in your build script. – medmunds May 24 '16 at 02:08

Philip Tzou · Answer 5 · 2016-07-12T19:32:20.443

5

I think the simplest solution here is just run Python with xvfb-run:

sudo apt-get install xvfb
xvfb-run python <your_file_or_args>

edited Jul 12 '16 at 19:32

answered Jan 07 '16 at 08:23

Philip Tzou

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27

Could you give a quick explanation as to what running python via xvfb-run does? The manpage isn't very helpful – YPCrumble Jun 09 '16 at 05:53
1

@YPCrumble xvfb has nothing to do with the executable running inside. The problem is about the selenium version or the firefox used with it. Best way to solve this kind of problems is to attach a copy of firefox with your script instead of run your script inside a environment that you don't control/know. – m3nda Jun 12 '16 at 16:01
@YPCrumble per your question, xvfb-run is same than pipe anything to xvfb, but in a reverse way. – m3nda Jun 12 '16 at 16:02

score 1 · Answer 6 · answered Jun 13 '16 at 18:28

Rollback your Firefox to the previous working version. I suggest 2 versions back. Disable Firefox Maintenance Service.

I was working on a solution and the Firefox Maintenance Service updated Firefox to the latest build in the background. This broke my code and it was giving me this error.

Now it is fixed!

Thank you everyone!

score 1 · Answer 7 · edited Jul 14 '16 at 07:12

1

This error is due to your Xvfb is not running. So restart your xvfb:

Xvfb :99 -ac

then check. This works for me.

edited Jul 14 '16 at 07:12

Nander Speerstra

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answered Jul 14 '16 at 06:44

Ashok Devatwal

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15

valignatev · Answer 8 · 2016-07-23T04:15:12.810

Instead of downgrading firefox from 47 version to 45 or something I'll suggest to upgrade to 47.0.1 or above since they seem to fix an issue.

But if your OS doesn't have new packages in repo (for example Ubuntu 14.04 in time of this answer), you can use debs from ubuntuzilla project:

wget sourceforge.net/projects/ubuntuzilla/files/mozilla/apt/pool/main/f/firefox-mozilla-build/firefox-mozilla-build_47.0.1-0ubuntu1_amd64.deb

sudo dpkg -i firefox-mozilla-build_47.0.1-0ubuntu1_amd64.deb

For x86 use _i386.deb postfix. That sold problem for me

score 0 · Answer 9 · answered Nov 18 '14 at 07:50

0

I fixed this by running a recursive chown against not only the python script using selenium, but against the entire virtualenv that script was running in. I changed the ownership to the user running the file. After that, this error went away.

answered Nov 18 '14 at 07:50

melchoir55

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score 0 · Answer 10 · answered Aug 25 '16 at 05:34

I also faced the same issue, what I did was:

Upgrade selenium package
```
sudo pip install -U selenium
```
Instead of rolling back to older version(like suggested) I rolled up to newer version(48.0, I was previously using V47.0). (for upgrading follow the instructions given by Toby Speight but instead of choosing older version choose newer version)

score 0 · Answer 11 · answered Nov 08 '20 at 14:12

I found this solution on Windows 10 Build 18363. I had to call out specifically the Firefoxbinary and the geckdriver executable path.

from selenium import webdriver
from selenium.webdriver.firefox.firefox_binary import FirefoxBinary
from selenium.webdriver.common.desired_capabilities import DesiredCapabilities
caps = DesiredCapabilities.FIREFOX.copy()
caps['marionette'] = True

# Path to Firefox binary
binary = FirefoxBinary(r'C:\Program Files\Mozilla Firefox\firefox.exe')

# Browser (driver) binary assigned, capabilities, and executable path for the geckodriver
driver = webdriver.Firefox(firefox_binary=binary, capabilities=caps,
                           executable_path=r'C:\Users\<name>\python\python-projects\geckodriver-v0.28.0-win64\geckodriver.exe')
# get google.co.in
driver.get("https://google.com")

score -2 · Answer 12 · answered Jun 06 '16 at 10:41

-2

update your selenuim version ---> pip install -U selenium

answered Jun 06 '16 at 10:41

ayoub laaziz

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score -7 · Answer 13 · edited Apr 30 '15 at 19:21

-7

It can be solved by changing the file permission of the output file ( or related files to the program).
I used Firefox's webdriver.

Try:

chmod -R 777 output_file

This solved me the same trouble you have.

edited Apr 30 '15 at 19:21

kenorb

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answered Oct 14 '14 at 06:55

ZodEnIX

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@ZodEnlX Oh Thank you for your comment!! It is the old post and actually I've given up for this. I should definitely try your solution!! which file's permission should I change? I mean, in your case, which file's permission did you change? – W3Q Oct 16 '14 at 15:58

How to fix Selenium WebDriverException: The browser appears to have exited before we could connect?

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