Forum Discussion
External Users Unable to Access Microsoft List Form
The behavior is expected: Microsoft Lists form links are intended for people inside the Microsoft 365 organization. Giving a guest Contribute access to the SharePoint list does not change that audience check, so no additional list, site, or sharing permission will make the dedicated form link work externally.
Your test confirms the SharePoint permissions are correct, because the guests can open the list and create items with + New. If Microsoft Forms is excluded, send guests to the SharePoint list’s New item experience instead. Keep the list shared with the required guests and use Contribute, or a custom permission level that includes Add Items, to match their required access.
Test the link with a separate guest after the invitation has been accepted. If the dedicated intake layout is mandatory, you will need a different front end that explicitly supports external respondents; the Microsoft Lists form settings cannot enable this.
The behavior is expected: Microsoft Lists form links are intended for people inside the Microsoft 365 organization. Giving a guest Contribute access to the SharePoint list does not change that audience check, so no additional list, site, or sharing permission will make the dedicated form link work externally.
Your test confirms the SharePoint permissions are correct, because the guests can open the list and create items with + New. If Microsoft Forms is excluded, send guests to the SharePoint list’s New item experience instead. Keep the list shared with the required guests and use Contribute, or a custom permission level that includes Add Items, to match their required access.
Test the link with a separate guest after the invitation has been accepted. If the dedicated intake layout is mandatory, you will need a different front end that explicitly supports external respondents; the Microsoft Lists form settings cannot enable this.