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After you've followed the invitation token from your national administrator, you'll be dropped right in the "Edit IdP" page. On that first time, you'll see a "wizard mode" which provides lots of explanatory text about the meaning of all the settings you can make. You can add and delete any of those options; don't be shy and try them all out! Adding a new option is done by pushing the corresponding button, selecting which option you want to set, and then the content of that new option. Changes will only be saved when you hit the "Continue ..." button on the bottom of the page.
When you re-visit the "Edit IdP" page later from the Institution Overview page, the explanatory texts are condensed in order not to overload the user interface. You'll certainly find your way around without the wizard texts.
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