If you forgot to backup certain documents (some people do) open the case, take the hard disk out, put it in an external enclosure so you can access it via USB and use another (your new?) PC to copy the files form that old hard disk.
You could consider to keep using that old hard disk in that enclosure to backup things to in the future.
Kees
Myself Joseph White Wolf, I am having a PC at my residence, with Windows 7 operating system, 2 gb RAM, 1 TB of hard disk capability, it is near about 3 years old. From the day before yesterday, it is not booting at all. I have many important documents and business related papers there within the PC. What shall I do?

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