In App Store, locate and install the Avaya IX Workplace app
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In the setup wizard, accept the prompts to allow the app to make and manage calls, access your microphone, etc.
Accept the software license
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Choose "configure my account"
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Select the gear in the upper right corner, and choose
"Use a Web Address"
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In the "Web Address" field, enter the following text: http://sm-onex.voip.me.edu/46xxsettings.txt
and click "next"
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The app will configure your settings and launch a quick tutorial.
Some things to note: Using the name directory may not always work, but entering an extension number should produce a dial.