after installing a clean windows 7 in my C drive my D drive says i need to format it to access it, but i never touched it and it had files i need is there anyway i can get my files back i haven't formatted the D disk yet i need your help
Does your D: drive have a disk letter? Have you tested it using Seagate's test tool? That video, which I watched, is only specific to his issue, it might not help you at all.
What are the specs of your system? The problem might not have anything to do with your D: drive and might be related to your motherboard. If you have a modern system then you need to run Windows 10 or you will never be able to access your D: drive.