Hi @ChrisPo 布錦聲 ,
Thanks for your post! This depends on whether or not you are enforcing Office 365 identity in your network. If so, all Office 365 users that have a Yammer license are created as pending users in Yammer. Otherwise if you are not enforcing Office 365 identity, users will not be part of the Yammer network until they have selected the Yammer tile from Office 365 or signed in once to Yammer.
To enforce Office 365 identity, you can follow these steps:
1) In Yammer, go to Network Admin and select Security Settings.
2) In the Security Settings page, go to the Office 365 Identity Enforcement section and select Enforce Office 365 identity. You must be both a Yammer verified administrator and a global administrator to see this section. There you can select additional settings for how you want to enforce this policy.
If you are not enforcing Office 365 identity, you will have to invite users the normal way by selecting either email addresses or bulk-inviting using a CSV file and selecting based on other criteria such as job title and name.
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