Enabling federation / external access for Office 365

To enable federation/external access (i.e. communication with outside parties) for Office 365:

  1. Go to https://portal.office.com and login with a user that has Administrator credentials.
  2. Select the tiles button in the upper left of the screen. Then select the gray Admin button to take you to the Admin center.

  3. Within the Admin center, select Admin centers labeled #1 in the picture below. Then select Skype for Business labeled #2 in the picture.

    The Skype for Business admin center opens in a new window.

  4. Set your federation options within the Skype for Business admin center:

    1. Select organization labeled #1 in the picture below.
    2. Select external communications labeled #2 within the picture.
    3. There is a pulldown menu under external access. We recommend selecting On except for blocked domains to allow communication with all outside parties, as shown in #3.
    4. You can optionally select the option labeled in #4 to allow complete federation with users outside your organization.
    5. Scroll to the bottom of the page and select Save.

While there is no published guidance we are aware of, we have found success in waiting 24 hours for these settings to fully propagate in Office 365.