Trying to automate a Multilogin browser profile with Selenium, but your script won't connect? First, check that the profile started successfully and that your script is using the right connection port.

➡️ In your script, find the “Start Browser Profile” request → check automation_type=selenium → get data.port from the response → connect using webdriver.Remote.

Multilogin uses Remote WebDriver to connect Selenium to your running Mimic browser profile. If you use webdriver.Chrome() instead, Selenium starts a separate browser rather than connecting to your Multilogin profile.

Check your browser profile launch

Before troubleshooting Selenium, make sure Multilogin can start your browser profile. If the profile doesn't launch, there's nothing for your script to connect to.

Check these details:

1. Multilogin is running: make sure the desktop app is open
2. Profile IDs are correct: check that you're using the right folder ID and profile ID
3. API token is valid: make sure your request includes a working token
4. Endpoint is correct: use the “Start Browser Profile” request
5. Automation is enabled: set automation_type=selenium

Here's an example of the start request:

GET https://launcher.mlx.yt:45001/api/v2/profile/f/{folder_id}/p/{profile_id}/start?automation_type=selenium&headless_mode=false

Replace {folder_id} and {profile_id} with your actual IDs.

When the request succeeds, Multilogin starts your Mimic browser profile and returns its connection details, including data.port.

Connect Selenium to your Mimic browser profile

Once your profile is running, Selenium needs to connect to that same browser session.

Use webdriver.Remote with the port returned by Multilogin. Since Mimic is Chromium-based, you'll also need ChromiumOptions().

Here's what the connection looks like in Python:

from selenium import webdriverfrom selenium.webdriver.chromium.options import ChromiumOptionsdriver = webdriver.Remote(    command_executor=f"http://127.0.0.1:{port}",    options=ChromiumOptions())

Here, port is the value returned in data.port when you started the profile.

A few things to keep in mind:

• Use the latest port: it can change when you restart a profile, so don't hardcode it into your script
• Wait for the profile to start: connect only after the API confirms that the start request succeeded
• Keep the profile running: Selenium needs an active browser session to connect to

You don't need another computer to use Remote WebDriver. The connection runs locally through 127.0.0.1.

You also don't need to launch a separate ChromeDriver or manually match its version to Mimic. Multilogin starts the browser session and gives Selenium the connection port.

Check your firewall and antivirus settings

If your browser profile starts but Selenium still can't connect, your firewall or antivirus might be blocking the local connection.

Here's what to try:

1. Check whether your firewall or antivirus is blocking local connections
2. Make sure connections between your script and Multilogin are allowed through 127.0.0.1 and the returned port
3. Run your script again to see if the connection works

You don't need to turn off your security software. Check its settings and add an exception if needed.

Check other possible connection issues

Still getting errors? A few other things can prevent your script from connecting:

• API errors: check the response status and body for details about what went wrong
• Authentication: make sure your API token hasn't expired
• Profile access: check that your workspace role allows you to start the profile
• Multilogin logs: look for errors that might explain why the browser couldn't start or connect

If you're not sure whether your script is set up correctly, compare it with the Selenium automation example.

You can also check the Multilogin API documentation for the required request parameters and response details.