I kill fb_inet_server.exe because sometimes database not go into shutdown state or not go into on-line mode, I don't know what, but something hold database so no one can work with database. If I kill fb_inet_server.exe the database goes to shutdown mode or in on-line mode. I may see this behavior on some windows servers with classic or superclassic FB.
I use 2.5.2.26540 FB server.