Hi Ritesh,
I am using the same microcontroller P89V51RD2 in my MC kit , and I am using the “Flash Magic” software to burn/dump the hex file to MC . My Os is Windows 7. The software works fine even with Windows 8 release preview. What kind of an error are u getting. Please check once again whether u have selected the “P89V51RD2” in Select Device button , Baud rate – 9600, Interface- Non-ISP, in Flash Magic software and the specific COM port for your PC.
Check it out once again .. and if u get the error Post the error message.
Bye 