AP1972
Try using this tutorial.
Hope this helps restore your device.
http://en.miui.com/thread-2100147-1-1.html

Hi thanks for your response. Here my first issue is device not detected by laptop.
Getting error : Unknown USB device (Device Descriptor Request Failed).
I have changed laptops changed usb cables. Today even changed entire charging usb sub board (sub board which having usb port). Installed all usb drivers. Adb driver and Qualcomm driver.. Still no use. Same error Unknown USB device (Device Descriptor Request Failed).
So device not detected means I can't flash os in any mode or repair IMEI numbers..
Is there any way to flash os flash files through memory card.
Thanks alot
Regards
Nazeer S