My previous problem is solved. I had forgotten to install "asm" program!. Now I have another problem. When I Compile my program, at end of compilation, it reports an error that can not find following files: GMain referenced from term.cmx Winfo referenced from functions.cmx GBin referenced from term.cmx GButton referenced from term.cmx GtkText referenced from term.cmx Glib referenced from term.cmx Tk referenced from functions.cmx GTree referenced from term.cmx GMisc referenced from term.cmx GdkEvent referenced from term.cmx Crosstable referenced from parser.cmx GPack referenced from term.cmx GtkSignal referenced from term.cmx Str referenced from table.cmx GText referenced from term.cmx GEdit referenced from term.cmx Gobject referenced from term.cmx Canvas referenced from functions.cmx GdkKeysyms referenced from term.cmx GWindow referenced from term.cmx GMenu referenced from term.cmx I think that I should add a library to OCaml. But what is this library? How can I find it? How can I install it? Thank you, Karimi