Are you working with Office365 and an ACP (Audio Conferencing Provider)? If so, you could call in with a PSTN phone using the phone number the ACP provided. If you use a Lync approved phone, you could potentially connect as well, but not
by dialing the number of the meeting, or any other number as this would be considered enterprise voice. You would typically connect by using your Lync client and the better together experience to join the meeting. In this scenario, a USB device
might be better and cheaper than an IP phone.
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SWC Unified Communications
This forum post is based upon my personal experience and does not necessarily reflect the opinion or view of Microsoft, its employees, or other MVPs.
