M365 Forms for external users

Copper Contributor

Our organisation is hosting a public event where we'd like people to vote on some ideas and guidelines for our organisation. We want to make sure everyone can vote exactly one time on each poll. We have all the email adresses in an Excel file since it was asked for registration to the event, if that helps. 


Is there a M365 functionality that would help us achieve our goal? Sadly, Forms doesn't register email adresses for external users even if we add them as guest in our Azure AD, so we can't restrict people voting only once as far as I know. So I'm looking for a Forms-like app in M365 that has this functionality, ideally in M365, but if M365 doesn't have this we're willing to look for external apps.


1 Reply

@mgiguere unfortunately there is nothing in M365 which will do what you want. With Forms you can't restrict external users to only 1 response since Forms doesn't know who the responder is. The only thing you can do within M365 is to have a form where you ask the user for their email address. A flow in Power Auotmate then checks a list to see if that email address has previously been used. If it has then do nothing. If it hasn't then add the email address to the list and add the form reponse to your "responses" list.


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