Invitations to the extranet group do not go away. How to decide?

Question

1C-Bitrix

When inviting a new employee to the group by e-mail, I ran into a problem that letters with an invitation link are not generated in Bitrix. They thought the point was that the letters go only to the internal mail of the company. We created a user with personal mail - letters go away. We looked at the logs - yes, how the user was created in the Bitrix admin panel, and in the postfix logs there is no log of sending a letter.

Answer 1

that letters with an invitation link are not generated in Bitrix

Formed but not logged
Are you sending via postfix? Or do you have BitrixEnv (the default is msmtp)?