Users who are in the "Everyone" or "Everyone except external users" group don't receive email invitations
Consider the following scenario:
You share a Microsoft SharePoint Online resource with the Everyone or Everyone except external users group.
You select the Send an email invitation option.
In this scenario, users who are in the Everyone or Everyone except external users group don't receive the email invitation.
This is expected behavior in SharePoint Online. When you share a resource in SharePoint Online, users in the Everyone or Everyone except external users groups don't receive email invitations when you specify either group while the Send an email invitation option is selected.
For more information, go to the following Microsoft website:
While the Everyone or Everyone except external users groups are most common, other groups are also affected by this scenario. Groups that are created in the Microsoft 365 admin center and security groups that are imported from local Active Directory by using Directory Synchronization will also experience this behavior.
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