The computer stores information like a library. In order to find a book 1st the book needs to there, and also stored in the correct place, and index by a catalog directory. Without these basic 3 structures in place it will be very difficult to get a particular book. What would happen if all the books where there but scattered everywhere? How would you find a book if they all looked the same and had no numbers? If there were millions of books how could you find one without a catalog directory. The system 32 is like a shelve in the library, the book a file, the catalog the windows registry. Just putting books back on the shelve without correcting the directory / registry is useless. So when repairing adding new books / files to a directory /shelve the windows registry also needs to be repaired. This is why by just copying new files into directories will not help. You need to use special system , registry repair utilities that can handle millions of files / and registry corrections. Always do back ups of important files and keep in separate place. In case of OS system failure you can reinstall OS , applications , and last your important SAVED files.

They can't really be "fixed" but you can go get good ones. 1) You could try running the System File Checker with the "Scannow" command switch. This will check and replace certain important files. http://www.bleepingcomputer.com/forums/topic43051.html 2) You could go to an earlier restore point, hoping it's mostly registry errors. http://www.microsoft.com/windowsxp/using/helpandsupport/getstarted/ballew_03may19.mspx 3) You could try running a repair install. http://www.microsoft.com/windowsxp/using/helpandsupport/learnmore/tips/doug92.mspx 4) Some other decent suggestions: http://www.help2go.com/Tutorials/Windows/C:%5Cwindows%5Csystem32%5Cconfig%5Csystem_missing_or_corrupt.html