A request was received by the RPC server on %1 endpoint from %2. The request was received on an unauthenticated channel, ...

A request was received by the RPC server on %1 endpoint from %2. The request
was received on an unauthenticated channel, but the registered endpoint requires 
that the request be made over an authenticated channel. This request will be 
ignored. The binary data contains the first 32 bytes of the request.