Hello NamLQ,
I have been facing the same problem… I couldn’t find the file to setting the admin user, with email.
I installed the actual Galaxy Docker version and, different from older versions, there’s no galaxy.yml file, just a galaxy.yml.sample… How did you fix it, or yet, did you update the Galaxy Docker recently?
Thanks for your help.
My wishes
Leandro
Yes, the Galaxy Docker Image was recently updated and is how it works is a bit different. There is a base installation that is then exported to a Galaxy server instance (one or more).
After a long pause, due to interesting times at the beginning of the “golden 2020s”, we are finally back with release 24.1. Many things have changed in Galaxy. It is deployed completely differently and gained many new features with many new dependencies. We recommend starting with a fresh /export folder and contacting us if you encounter any problems.
The README in the repository includes all of the details. This is the section with the instructions for updating the admin_user credentials, and the other two relevant keys.
But maybe back up at start at the top to learn about how the image is different? If you have any questions, you can ask here and we’ll try to help more! Should you run into a bug, please submit an issue at the repository.
If am misunderstanding something, and you started up the server following the new instructions, we can get some clarity by bringing in more help here.
Hope this helps! 
Thank you so much @jennaj . I’ve set the admin user now. It’s working perfectly.
Great, thanks for letting us know @lfdeoliveira 