Programming PIC24FJ64GB004

Hello all, I am trying to run simple LED blink program on PIC24FJ64GB004(bought from http://www.kynix.com/Detail/416542/PIC24FJ64GB004T-I-ML.html)using PICKit3 programmer. 

I tried multiple codes but all give same response. When i write a 0 to GPIO it remains at logic 0, but when i write 1 to any GPIO it starts toggling. 
Same behavior whatever configuration or code i try whatever GPIO i use. 
Please suggest me where is the issue. Below is one of the codes i've tried but no luck. Please help me out. Thanks all.

#include <p24fxxxx.h>
_CONFIG1( JTAGEN_OFF & //JTAG port is disabled

             GCP_OFF & //GSP Memory Code Protection OFF

             GWRP_OFF & //GCC Flash Write Protection OFF
             FWDTEN_OFF & //Watchdog Timer OFF
             ICS_PGx1) //debug over PGD1 and PGC1

_CONFIG2( FNOSC_FRCPLL & //Internal FRC with PLL
             OSCIOFNC_ON & //RA3 is clk out (fosc/2)
             POSCMOD_NONE & //Primary oscillator disabled
             I2C1SEL_PRI) //Use default SCL1/SDA1 pins



#pragma code

int main(void)
{
   unsigned long i; //a 32 bit variable to use as a timer

   CLKDIVbits.RCDIV0=0; //clock divider to 0
   AD1PCFG = 0xFFFF; // Default all pins to digital
   OSCCONbits.SOSCEN=0; //Disables the secondary oscilator

   TRISAbits.TRISA1 = 0; //sets the Mode LED pin RA1 as output
   LATAbits.LATA1 = 1; //turns LED ON

//////////////////////////////////////////////////////////////////
///FOREVER LOOP///////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////
    while(1)
    {

    } 
}