Problem with registry

I was deleting certain files in my registry and I accidentaly deleted the “Microsoft” file (In one of the software files in hkey local or hkey ) and my computer cannot boot up and it just keeps restarting. After 3 times it goes into recovery.

What I’ve tried:
1. Reinstalling windows through usb, “Cannot mount file”
2. Reset this pc “Requires more storage space”
3. Tried freeing up more storage space by deleting files in program files but nothing changes but the files do get deleted (I think it tries to go to recycle bin but I can’t open recycle bin even through command prompt)
4. I have no restore point
5. I cannot go back to a previous version

So in summary I’m stuck with a corrupted registry and a non-booting computer

If anyone can help that would be great
 
My first inclination is to hit it in the head 3x with a hammer, but my spouse assures me that only results in a pile of broken pieces... so we won't go there.

1. Buy new storage (good time for a 250GB SSD)
2. Replace old HDD with new.
3. Install OS fresh
4. Reinstall old storage as a second 'data' drive
5. Take ownership of the old storage - make back ups - reinstall other apps - make restore point, etc
6. Be thankful you didn't follow my first idea.
 
The hammer is always saved for the last resort

Do the sizes of the SSD matter? (The physical size of it)
Is there another way to avoid buying an £18 Kingston ssd?
Any other way using software?
 
While you could hunt lions with a .22, I think you want at least a 30/30. 128GB would be large enough, but prices are very reduced so 256GB is not prohibitive.

You might run Linux from a flashdrive.
 
If pinched for funds, you can install your storage drive in another computer and use that to recover your data files. Then reinstall your drive and install your OS fresh.
 
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