"SessionNotCreatedException: Message: None" under Python 3.12.0

Hello, I have updated my python from version 3.9.9 to version 3.12.0 and with it all my Robotframework dependencies on my Windows machine.
When launching “Open Browser” to launch my tests on a private server I am receiving the error “SessionNotCreatedException: Message: None” without any explanation beyond this simple message. I’m not sure if this is a version incompatibility as I’m not getting any help from the error message.

How I launch my tests running in Python 3.9.9:

${chrome_options}=	Evaluate	sys.modules['selenium.webdriver'].ChromeOptions()	sys, selenium.webdriver										
Call Method	${chrome_options}	add_argument	--start-maximized										
Call Method	${chrome_options}	add_argument	--disable-notifications					
${prefs}	Create Dictionary	download.default_directory=${downloadDefaultDirectory}	useAutomationExtension=${FALSE}	download.prompt_for_download=${FALSE}	safebrowsing.enabled=${TRUE}	download.directory_upgrade=${TRUE}
Call Method	${chrome_options}	add_experimental_option	prefs	${prefs}									
${desired_capabilities}=	Create Dictionary	browserName=${browser}	userName=${userName}	token=${token}	pacAlias=${pacAlias}	video=true				
Open Browser	${url}	remote_url=${s_url}	options=${chrome_options}	desired_capabilities=${desired_capabilities}

Dependency list:

attrs                              23.2.0
autopep8                           2.1.0
beautifulsoup4                     4.12.3
cached-property                    1.5.2
certifi                            2024.2.2
cffi                               1.16.0
chardet                            5.2.0
charset-normalizer                 3.3.2
click                              8.1.7
colorama                           0.4.6
comtypes                           1.4.2
convertdate                        2.4.0
cryptography                       42.0.7
decorator                          5.1.1
defusedxml                         0.7.1
dnspython                          2.6.1
docutils                           0.21.2
et-xmlfile                         1.1.0
exchangelib                        5.4.0
fire                               0.6.0
fonttools                          4.51.0
fpdf2                              2.7.8
furl                               2.1.3
graphviz                           0.20.3
h11                                0.14.0
hijri-converter                    2.3.1
holidays                           0.48
htmldocx                           0.0.6
idna                               3.7
importlib_metadata                 7.1.0
isodate                            0.6.1
java-access-bridge-wrapper         1.2.0
jsonpath-ng                        1.6.1
jsonschema                         4.22.0
jsonschema-specifications          2023.12.1
korean-lunar-calendar              0.3.1
lxml                               5.2.2
more-itertools                     10.2.0
mss                                9.0.1
netsuitesdk                        2.21.3
notifiers                          1.3.3
O365                               2.0.34
oauthlib                           3.2.2
openpyxl                           3.1.2
orderedmultidict                   1.0.1
outcome                            1.3.0.post0
packaging                          24.0
pdfminer.six                       20231228
pendulum                           3.0.0
pillow                             10.3.0
pip                                24.0
platformdirs                       4.2.2
ply                                3.11
psutil                             5.9.8
pycodestyle                        2.11.1
pycparser                          2.22
Pygments                           2.18.0
PyJWT                              2.8.0
PyMeeus                            0.5.12
pynput-robocorp-fork               5.0.0
pyotp                              2.9.0
pypdf                              4.2.0
pyperclip                          1.8.2
Pypubsub                           4.0.3
PySocks                            1.7.1
pyspnego                           0.10.2
python-dateutil                    2.9.0.post0
python-docx                        1.1.2
python-dotenv                      1.0.1
pytz                               2024.1
pytz-deprecation-shim              0.1.0.post0
pywin32                            306
pywinauto                          0.6.8
PyYAML                             6.0.1
referencing                        0.35.1
requests                           2.31.0
requests-file                      2.0.0
requests-ntlm                      1.2.0
requests-oauthlib                  2.0.0
requests-toolbelt                  1.0.0
robocorp-storage                   1.0.4
robotframework                     7.0
robotframework-excellentlibrary    1.0.0
robotframework-pythonlibcore       4.4.1
robotframework-requests            0.9.7
robotframework-ride                2.0.8.1
robotframework-sapguilibrary       1.1
robotframework-seleniumlibrary     6.3.0
robotframework-seleniumtestability 2.1.0
rpaframework-core                  11.3.2
rpaframework-pdf                   7.3.2
rpaframework-windows               7.5.1
rpds-py                            0.18.1
selenium                           4.20.0
setuptools                         69.5.1
simple-salesforce                  1.12.6
six                                1.16.0
smartsheet-python-sdk              3.0.2
sniffio                            1.3.1
sortedcontainers                   2.4.0
soupsieve                          2.5
sspilib                            0.1.0
stringcase                         1.2.0
tenacity                           8.3.0
termcolor                          2.4.0
time-machine                       2.14.1
trio                               0.25.0
trio-websocket                     0.11.1
tweepy                             4.14.0
typing_extensions                  4.11.0
tzdata                             2024.1
tzlocal                            5.2
uiautomation                       2.0.18
urllib3                            2.2.1
validators                         0.28.1
webdriver-manager                  4.0.1
wrapt                              1.16.0
wsproto                            1.2.0
wxPython                           4.2.1
xlrd                               2.0.1
xlutils                            2.0.0
xlwt                               1.3.0
zeep                               4.2.1
zipp                               3.18.1
```

Hi Jose,

sorry for the delay.

The error message is coming from Selenium and is indeed not telling much. After your post SeleniumLibrary 6.4.0 got released mentioning that selenium had rearranged some settings and SeleniumLibrary fixed those for Open Browser keyword (see issue 1900). Maybe the new version already fixes the issue?

Furthermore, if it is a problem with the python version, SeleniumLibrary states on its readme that officially only Python up to 3.11 is supported. Maybe try downgrading to 3.11 then.

Regards,
Markus

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