If you enable this policy or leave it unset, Basic authentication challenges received over non-secure HTTP will be allowed. If you disable this policy, non-secure HTTP requests from the Basic authentication scheme are blocked, and only secure HTTPS is allowed. This policy setting is ignored (and Basic is always forbidden) if the 'AuthSchemes' (Supported authentication schemes) policy is set and does not include Basic.
Solution
Policy Path: Microsoft Edge\HTTP authentication Policy Setting Name: Allow Basic authentication for HTTP