Hi!
What is the meaning of training mode? Can you describe more details about it?
To my knowledge, Users can start or join an ad-hoc Skype for Business meeting easily in the Skype for Business client or in Office. Skype for Business lets users escalate simple instant messaging conversations or email conversations to PC-based, multiparty (three or more users) audio and video meetings with shared desktops, applications, and documents. For more details about Skype for Business meeting, you can refer to:
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