Hello @eksidouk! I'm sorry to hear you've encountered this error. I can see you've created another thread with this issue. I've merged the thread with the main topic about this error code.
I've had a look and this is an issue we're currently investigating. In the meantime, we've had reports from some players that changing the "UseProxyAutoDiscovery" value from 0 to 1 in GameSettings.ini file, resolved the issue for them.
You can find the file with the following path: Documents \My Games\Rainbow Six - Siege\ \GameSettings.ini
Please note that instead of the spot , you'll see a strings of numbers and letters. That's working as intended and should lead you to the settings file. Once you've changed the value in the file, be sure to save it for the change to take effect.
Please let me know if this workaround is able to resolve the issue for you!