System.InvalidOperationException (SessionNotCreated) and Browser Window opens non-automated on some machines

[andreas-neubacher]

When I drive Edge with Selenium (.NET) on a dev machine (Windows 11), everything works fine.

When I do the same on an office PC (also Windows 11), I get exception

System.InvalidOperationException: session not created: probably user data directory is already in use, please specify a unique value for --user-data-dir argument, or don't use --user-data-dir (SessionNotCreated)

but the browser windows still opens - apparently in non-automated mode.

I've tried all obvious variants: Specify a different user data dir, specify different profiles, make sure that there is no edge instance running in Taskmanager, try with the "Edge Dev" version, etc.

When I look at the driver logs and run the logged command line in a terminal, I do not see any errors, but also get different behavior.

Dev Machine (working as expected):

Office Machine (does not open in "automation mode"):

What could cause this different behavior?
Are there any command-line options that I could apply to make the webdriver work in all environments?

[abreland-amd]

Hey Andreas, I am seeing the same issue in the same environment. It only started happening to us yesterday, when we restarted our .NET server application that runs the selenium operations.

I tried specifying a unique user-data-dir for each new driver / browser instance, but then I get an error about the devtools port not being properly closed last time.

Curious if the EdgeDriver team have any feedback.

[andreas-neubacher]

No response yet.
Note that the issue is intermittent for me. Failed repeatedly, then worked for a few days, then failed continuously again.

Could not identify any pattern, yet.

[Gettokiwi]

Adding this to the options solved it for me for some reason, don't ask me why. But it works as a temporarily solution.

"--remote-debugging-port=9222"

[abreland-amd]

Thank you Gettokiwi, your fix worked for me with a slight adjustment. In my case, I am running multiple browsers concurrently so Selenium threw an exception when I tried to start a 2nd browser with the same debug port. I used the following bit of code from here to find a free port for each browser when I initialize them.