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Hi - I'm using External ID in an external tenant (customer) and wanting to provider a "sign up" link in an email. Ideally that would also prepopulates the users email address.
I've trying setting the "prompt=signup" in the oauth authorize request but get this error "AADSTS90023: Unsupported 'prompt' value.".
How can I achieve this using Entra External ID for customers?
Thanks
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Hello @Kevin,
Thank you for posting your query on Microsoft Q&A.
I understand that you're using an External ID tenant and have been providing a sign-up link via email, hoping to prepopulate the user's email address during sign-up. You attempted to use the prompt=signup parameter in the URL, which resulted in an error stating "Unsupported 'prompt' value."
The prompt=signup parameter is not supported. Instead of using prompt=signup, try adding the login_hint or prompt=select_account parameter in your sign-up URL.
Please test this approach and let me know how it works.
Thanks,
Raja Pothuraju.
Following up to see if the below suggestion was helpful. And, if you have any further query do let us know.