I was using my hdd on a lenovo thinkpad 420 and it was running on windows 10 and it was working fine. So I changed to HP Elitebook 8460p and I inserted my hdd but was malfunctioning. I tried formatting it but could not load windows 10 on it but I can format to windows 7. I removed the hdd and put in another elitebook 8460p and it worked very well on windows 10 after formatting the hdd but putting it back to my own hp, it doesn't boot but rather shows diagnostics repairs and doesn't get past there. Pls I need your help urgently.