Here are the needed steps to sign into the Outlook Web Application Webex Plugin
1> Sign into Microsoft 365
2> Open the calendar tab, click New Event, and click on the webex icon
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3> Select Add Webex Meeting
You will prompted to to Open another window in some browsers, please click allow which will open an Microsoft 365 sign-in prompt
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4> A prompt should appear to begin, you will want to click get started
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5> If prompted for your webex site please enter newpaltz.webex.com
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6> Then sign in using your Microsoft 365 credentials
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You may be prompted to sign in several times which is normal. This setup is only needed the first time you use the webex add-in.