I'm having a serious problem with allegro. The program should display random pixels on the screen and when I build and run it I get the following error message:

Below is the full code of my program:

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include "allegro.h"

#define Text_Color_Red makecol(255,0,0)
int main()
{
    int ret;
    int color_depth = 32;
    int x;
    int y;
    int red;
    int green;
    int blue;
    int color;

    //init allegro
    allegro_init();

    //install keyboard
    install_keyboard();

    //set color depth to 32 bits
    set_color_depth(color_depth);

    //init random seed
    srand(time(NULL));

    //init video mode to 640 x 480
    ret = set_gfx_mode(GFX_AUTODETECT_WINDOWED,640,480,0,0);

    if(ret !=0)
    {
        allegro_message(allegro_error);
        return 1;
    }

    //Display string
    textprintf(screen,font,0,0,10,0,Text_Color_Red,"Screen Resolution is: %dx%d -- Press ESC to quit !",SCREEN_W,SCREEN_H);

    //display pixels until ESC key is pressed
   //wait for keypress
    while(!key[KEY_ESC])
    {
        //set a random location
        x = 10 + rand() % (SCREEN_W-20);
        y = 10 + rand() % (SCREEN_H-20);
        //set a random color
        red = rand() % 255;
        green = rand() % 255;
        blue = rand() % 255;
        color = makecol(red,green,blue);
        //draw the pixel
        putpixel(screen, x, y, color);
    }

    //quit allegro
    allegro_exit();
}

END_OF_MAIN()

Error message: AllegroPixels1.exe has encountered a problem and needs to close. We are sorry for the inconvenience.

Error signature: AppName: allegropixels1.exe AppVer: 0.0.0.0 ModName: alleg42.dll ModVer: 4.2.3.0 Offset: 0006c05c

I am using Windows XP inside a virtual machine under Parallels 7.0