OcaIDE : Cannot exec ocamlrun

[nuaaysh]

when i run *.byte file ,
the console says "Cannot exec ocamlrun"
or
the Custom Toplevel says "Cannot exec ocamlrun
Process ended with exit value 2"

what should i do ?
i use ocaml version 4.01.0, windows 10 (by cygwin) eclipse version:LUNA
i follow "https://fdopen.github.io/opam-repository-mingw/installation/", install my ocaml.