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Option 2: Add an external user to Skype
1.Click "People with plus" button in your Skype for business:
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Page Comparison
General
Content
Integrations
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Option 2: Add an external user to Skype
1.Click "People with plus" button in your Skype for business:
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2. Select → "Add a contact not in my organization" → "Skype"
3. Search for the contact outside of Skype via their e-mail or Skype user name