I noticed that somebody posted this problem in December, but a solution was never posted. So, I thought I'd try again.
I'm using file sharing over TCP/IP and love it a lot. But, a few days ago I noticed that the check box to allow file sharing over TCP/IP was being unselected whenever the computer was shut down or turned off. File sharing itself stays on, but not file sharing via TCP/IP.
I have tried trashing the file sharing preferences file, the users and groups preferences file, the users and groups data file, and the finder preferences file, thinking one of them somehow became corrupted. So far, no luck fixing this.
This is a tremendous pain. Does anyone know how to fix this.