I'm supposed to have a legitimate Windows 10 copy since I had Windows 7 and could have upgraded to it. But my Windows 7 copy got a virus for some reason and was unable to be used. So I just pirated a Windows 10 copy so that I can continue using my laptop.
No, your usage of pirated version of Windows 10 is not halal.
As the Dr. Zakir Naik has put it in the linked video, piracy is haram and your case does not fall under the exceptional cases he has mentioned. Because,
It is not an established fact that Microsoft encourages pirating it's operating system.
As of this writing, anyone can use Windows 10 for free. It just will be in "not activated" state if one has not purchased a license or did not upgrade from a genuine version of Windows 7/8.
If you truly had a genuine version of Windows 7 and you have lost your key, you need to contact Microsoft to reclaim your original key. I am sure you can contact to their sales team through their website. Alternatively, you may contact a local representative office. Microsoft has offices around the globe, almost in all countries.
If you are not really required to use Microsoft Windows, there are free alternative operating systems (Linux being the most popular one). You may for example, use FreeBSD, Fedora, centOS, Debian, Ubuntu, LinuxMint or openSUSE instead. There is even one that resembles macOS - elementary OS.
I have done a research about your question as I also have a non-activated Windows 10 (not pirated). I have also listened to Dr. Zakir Naik's video about pirated software.
The answer is simple that your Windows 10 is not haraam as Microsoft allows piracy of Windows 10 in India and other developing countries (you can search on the Internet about it, just go and search "why does Microsoft allow piracy in India").
But I still recommend to use a non-activated Windows as Microsoft allows it too. That will be safer. Do not activate your Windows using softwares like KMS as Microsoft officially declares it illegal so that will be haraam.
I think it should be halal.bcecause it is the responsibility of windows to keep their software free from virus. Why should we purchase windows again and again. Let's my windows got a virus 10 times, should I purchase it 10 times. It is easier to say haram for those who don't understand the practical and technical side of it. So all pirated windows are halal according to me, because there was already a genuine windows before it was caught by a virus. Iam not a scholar,but I expect an answer from a scholar who know the fiqh as well as the technology. Jazakumullah
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