[Konstantinos]

Make sure that vehicleid is an integer. The code seems fine and it compiles fine as well.

pawn Код:

#define VEHICLE_PATH "%i.ini"

public OnFilterScriptInit( )
{
    new INI:file = INI_Open (VehiclePath(1));//ERROR LINE
    return 1;
}

stock VehiclePath (vehicleid)
{
    new string[128];
    format(string,sizeof(string),VEHICLE_PATH,vehicleid);
    return string;
}