The HDD of my Dell PC (XPS 8500) crashed, I replaced the HDD. This PC came with Windows 8 and I upgrade to Windows 8Pro and free upgrade to Windows 10. Now how I can retrieve Product Key for reinstalling Windows 10, Any help will be appreciated in this regard?
If you installed windows 10 and activated you will not need any key.
You can choose the option to "Skip entering a key" and reinstall from scratch and once you get online it will become re-activated.
Oem media will not have this option.
It's still possible to pre-install Windows 8.x or Windows 10 with a generic key. These keys can only install Windows. It's not possible to activate it unless you enter an original key purchased from Microsoft or you did the July update and activated before the cutoff.
XKY4K-2NRWR-8F6P2-448RF-CRYQH (Windows 8 Professional)
RR3BN-3YY9P-9D7FC-7J4YF-QGJXW (Windows 8 Professional with Media Center)
FB4WR-32NVD-4RW79-XQFWH-CYQG3 (Windows 8 [Home])
XHQ8N-C3MCJ-RQXB6-WCHYG-C9WKB (Windows 8.1 Pro)
GBFNG-2X3TC-8R27F-RMKYB-JK7QT (Windows 8.1 Pro MCE)
334NH-RXG76-64THK-C7CKG-D3VPT (Windows 8.1 [Home])
VK7JG-NPHTM-C97JM-9MPGT-3V66T (Windows 10 Pro)
YTMG3-N6DKC-DKB77-7M9GH-8HVX7 (Windows 10 Home - multi language)
BT79Q-G7N6G-PGBYW-4YWX6-6F4BT (Windows 10 Home - single language)