[Fixed] :)

After a lot of tests (some of them with very litle sense, you would laugh at me but dispair makes that) I have found the answer: ¡¡path with forward slashes AND ended with slash!!. with or without ", with a single or double // are the same. safe_mode_exec_dir = c:/wwwroot/tests/bin/ safe_mode_exec_dir = "c:/wwwroot/tests/bin/" safe_mode_exec_dir = c://wwwroot//tests//bin// The absolut path in exec() or system() is unnecessary.