Problem creating a group in Outlook 365

[Guido Harten]

I want to create a mail group in my Office 365 Essential. The group consists of internal and external email addresses of team members.

All addresses should be able to use the group address to send emails to the whole group.

It seems I only can add internal addresses. How can I do to add external addresses?

Regards,

Guido van Harten

[#2]

Guests need to be invited first, and the tenant settings need to allow for Guest invitation. Read here: https://support.office.com/en-us/article/guest-access-in-office-365-groups-bfc7a840-868f-4fd6-a390-f...