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Click on Extensions --> groups
If you are creating a new Group/Department - check the Department option, and fill out all the other fields. You may wish to read How to: Configure HUD Permissions which describes the permissions process in detail and uses the HUD2 application as a reference.
Assign your Department an Extension number (this extension will be used when you perform a Group Page or Group Intercom, etc.)
Add people to your Department
Add permissions to your Department
Add the group or groups at the bottom that the individuals at the top have permissions over
Click Create Group / Department
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