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You will need to provide an Item ID and configure Redirect URIs when your are adding Connectors in the "Manage Identities" tab in the Clean My Org or Backup My Org application. This applies to ArcGIS Online or non-IWA (Oauth2) Authentication.
Step-by-step guide
STEP 11A (for ArcGIS Online): From the "My Content" tab, select "New Item"
(Select the "Application" option in the next step)
(Select the "Other Application" option in the next step)
STEP 1B (for ArcGIS Enterprise): From the "My Content" tab, select "Add New Item → An applicationApplication → Other Application."
(Select the "application" option in the new popup box)
(Select the "Application" option in the next step)
STEP 2: Call it "Clean My Org," or "Backup My Org" based on which solution you're using.
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