SOLVED: The provided URI scheme 'http' is invalid; expected 'https'. Parameter name: via

You receive the error message:

The provided URI scheme 'http' is invalid; expected 'https'.
Parameter name: via

… while using WCF to connect to an endpoint.

Probably you are trying to send a a username and password to authenticate although the connection is not secure (no HTTPS).

This modified binding should help:

<binding name="UserPasswordBinding">
security mode="TransportCredentialOnly">
transport clientCredentialType="Basic" />
/security>
/binding>