A really annoying error which is hard to understand until it is explained and then it makes perfect sense!
I was getting this on Azure when calling from a web application to a web service.
What it means is that the client endpoint you have specified (the "provided URI") has a scheme of https at the begining (the client url is https://whatever) whereas the meta-data for the endpoint that you probably added with "Add Service Reference" discovered that the protocol was http on the service binding. I got this with a client config in the web app of:

<endpoint address="https://6ead981357238479hfc0beff3193e7b.cloudapp.net/WebService.svc/standard"
binding="wsHttpBinding" bindingConfiguration="standard" contract="IWebService"
name="standard">
<identity>
<servicePrincipalName value="host/RD00443D49795E" />
</identity>
</endpoint>

And a service configuration of:

<binding name="standardConfig" maxReceivedMessageSize="65536000">
<readerQuotas maxDepth="32"
maxStringContentLength="65536000"
maxArrayLength="65536000"
maxBytesPerRead="65536000"
maxNameTableCharCount="65536000" />
</binding>

The fix is either to specify http on the client endpoint in the web application or to add <security mode="transport"> to the binding on the web service:

<binding name="standardConfig" maxReceivedMessageSize="65536000">
<security mode="Transport"></security>
<readerQuotas maxDepth="32"
maxStringContentLength="65536000"
maxArrayLength="65536000"
maxBytesPerRead="65536000"
maxNameTableCharCount="65536000" />
</binding>

If you do modify the service binding, you will need to update the service reference on the web app to ensure it now knows that the expected scheme is https.