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Step 2 - Do a Developer Registration
Fill out the form at Go to https://docs.superoffice.com/apps/getting-started/developer-registration-form.html and find the link Register as a developer that will take you to the form shown below. Fill out the blank text fields with your data and check off the check boxes select the same two radio buttons as shown below in the screenshot:
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Click OK and wait for SuperOffice to get back with you on the email address you gave above.
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The REST API URL is obtained from the status page as described in Status page Tenant status (the URL will be of this format https://servername.superoffice.com/Cust12345/api/v1/)
The Client ID is obtained as described in What is my client ID?
The Client Secret is obtained as described in Create a new client secret
The username and password of the SuperOffice user