[Windows Central Question]

If my Nokia Lumia 530 dual sim crashes when upgrading to windows 10 what will I do

[Gaurav Sag]

you can try this

Download and install latest Nokia Software Updater For Retail

Run NSU and this window will pop up. Then click "My device does not boot up"

Now connect the phone that has been stuck at spinning gears via USB cable (make sure its fully charged) and click continue.

After connecting the phone, this will show up . Now press and hold the power and the volume down button until the phone vibrates. Your PC will detect a new hardware and will install the required drivers if needed. Then click Ok.
NSU will take over from here and will reflash your phone with a hefty 1.2GB of firmware download from its server. Let it finish and then you're done.