回複：收到侮辱性的email查到他的ip

I don't know law. But my sense is you can consult a lawyer and deal with the company or call the company directly. The comnpany has the liability to control the useage of the emaill system and company facilities. They should be able to help you find the sender and execute the company's policy. Most companies forbid these type of behavior and may fire the responsible employee.