Hi SKaero,
Thanks for getting back,
Thunderbird is connecting to mail.xxxx.org but the address mail is obviously aaaa@xxxx.org.
But in roundcube config file, it's xxxx.org (username domain)
For security, I'm using STARTTLS with normal password.
Not sure which kind of info can help...
EDIT: May be something is blocking localhost access? (From local network and internet, I can use Thunderbird or K-9 on Android)