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I have a domain name on DNSimple, with email forwarding to my Gmail account.
It's working well, except I would like to be able to send emails from Gmail using my DNSimple's email.
But when I go on Gmail settings, and click the Add another email address you own link and set my DNSimple email and Next step button, Gmail ask me for an SMTP password. And I have no idea about it.
If I correctly remember, at the beginning of Gmail it was automatic.