AD Connector, Request Schema doesn't work

Using these versions

I just created an AD Agent and then created a connector, gave it a name and set the Object Container

and as soon as the created Connector comes up, it has an error "This connector requires at least one key".

I hit request schema and get this error:

I added sAMAccountName as a the key and required and the error "This connector requires at least one key" goes away but when I request the schema I still get the above, "Value cannot be null. Parameter name: key"