Using security groups, you can assign permissions to security groups in the Active Directory or on resources. Security group -Security groups are used to control access to shared resources. The options, Security group and, Dynamic distribution group are not covered by this knowledge article. In the Exchange admin center, click the New icon, then select Distribution group.The Exchange admin center opens, on the groups page, in another window.
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If you or someone in your organisation sends email to a lot of users at once, you can send to a distribution group so you don't exceed the maximum number of recipients per message.You can also specify whether users outside of your organisation send email to a distribution group. You can specify which users in your organisation can send email to a distribution group. They help people inside and outside your organisation communicate and collaborate more easily.They make it easy to send an email message to lots of people at once.
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However, only external users that have been added to your organisation's address book (also known as shared contacts), can be members of a group. Internal users (users that have a mailbox in your organisation) and external users (people that don't have a mailbox in you organisation) can be added as members of a distribution group. An Office 365 administrator can create and manage distribution groups for an organisation. When an email message is sent to a distribution group, it goes to all members of the group. Creating and modifying a distribution group in Office 365Ī distribution group, or distribution list, is a collection of two or more people that appears in your organisation's address book.