A tool that checks for missing Registry Keys?

Hello,
I have a computer that has a corrupt registry. SFC /SCANNOW will not run. Windows Update will not work, Error Code 80080005. I even took my computer to a professional, dispite being very good with computers. He came back with the same result I did, a complete re-install of Windows. If I want Windows Update or SFC /SCANNOW to work again. Everything else with the computer works fine.

My question is, is there any way to repair the Windows Registry without doing a re-install?
SFC /SCANNOW finds missing/corrupt Windows Files.

Why isn't there a tool that finds and finds missing/corrupt Registry entries and replaces them? The only thing we have is a registry cleaner, which removes entries. I need something that scans for missing entries.

If there is no tool like this, why not? Is it impossible to make?

If there is no tool like this, why not? Is it impossible to make?

There is no such tool because for all practical purposes this would be impossible.

The core system files in the many millions of Windows 7 systems are all pretty much the same. The system was designed that way. But the registry is a very different kind of animal. It is a database that contains information that is specific to an individual computers hardware, drivers, and installed applications. A registry key serves a container for registry values, like a folder is a container for files. While the individual registry keys may be quite similar to those in other computers the values that inhabit them are very different.