ArcGIS Online: Failed to create OAuth connection. ClientError - Access to this application has been blocked

Error Message

Attempts to connect to the built-in ArcGIS Survey123 connector in Microsoft Power Automate fail, and return the following error:

Error:
Failed to create OAuth connection: ClientError: Access to this application has been blocked. Please contact your administrator to allow access to this app.

Cause

The ArcGIS Online organization restricts member access to external applications by enabling the 'Members can only sign in to external apps that are approved' function in the ArcGIS Online security settings. This setting ensures only trusted and pre-approved applications can access the organization's resources and protects sensitive data from potentially unsafe external applications.

Solution or Workaround

To resolve the issue, disable the Members can only sign in to external apps that are approved setting in ArcGIS Online. For instructions, refer to ArcGIS Online: Approve apps, and in Step 4, toggle the option off.

However, in cases where this function must be enabled for security considerations, create a custom ArcGIS Survey123 connector by registering the app in ArcGIS Online and using the app as the custom connector in Microsoft Power Automate. For instructions, refer to How To: Create an ArcGIS Survey123 connector for Microsoft Power Automate for use with ArcGIS Enterprise while replacing the parameter of the URL with the ArcGIS Online URL. The complete URL is as follows:

https://survey123.arcgis.com/api/template/swagger?portalUrl=https://www.arcgis.com