Comment by giuliomagnifico
1 day ago
Oh, thank you. I didn't know that. Anyway, I'm not using a custom domain on mailbox, I use my custom mail domain with another service.
1 day ago
Oh, thank you. I didn't know that. Anyway, I'm not using a custom domain on mailbox, I use my custom mail domain with another service.
Unfortunately this is common in many smtp servers and is configuration dependent: After you authenticate as usera@example.com you can send emails as userb@example.com.