[newbie scripter]

i'm getting this error when i include
y_ini or physics in my GM

Code:

y_debug.inc(114) : fatal error 100: cannot read from file: "internal\y_funcinc"

but i have another zombie GM in which it has y_ini but i don't get the error.

here is my includes,

Code:

native WP_Hash(buffer[], len, const str[]);

#include <a_samp>
#include <zcmd>
#include <sscanf2>
#include <explosions>
#include <mapandreas>
#include <physics>
#include <YSI\y_ini>

what could've been the problem?
i tried removing either physics or y_ini and tried compiling but it failed. any idea?