recovering windows 8.1 on my laptop where the HDD corrupted and no data is retrieved

[PVS Rao]

I purchased a DELL laptop with windows 8.1.Later it was upgraded to windows 10 during the validity period. Now the HDD of my laptop is corrupted and no data can be retrieved. I have installed a new HDD on my laptop. Now the question is, Can I get back my windows 10 or at least windows 8.1 on my laptop, since no key is available. When I contacted the DELL people they suggested me contact their service centre, where I was informed that it can not done since the the data on the old HDD can not retrieved. If the answer to my question is yes, How can I get back my OS? What is the procedure?

 

[bobmanuk]

if you download the windows 10 iso from Here and install it, it will activate it for you without needing a key.

If you upgraded within the free period then microsoft will activate windows 10 to the same version again.