Electric Make (eMake) generates this error when it fails to receive an A2E_ACK message from an agent during the initial connection handshake with that agent.
The handshake consists of several messages, with a few E2A_SYNC/A2E_ACK pairs at specific points during the sequence. One such point is following the E2A_SET_TIME message. eMake sends the sequence E2A_SET_TIME, E2A_SYNC; and it expects the agent to respond with A2E_ACK. This error code indicates that the agent replied with some other command code.