Now comes the scary part. The registry is the heart of any windows system and a dirty registry is the cause of most gradual loss of performance in an operating system. Rubbish (gunk) collecting in the registry (and it will collect over time) is like adding blind alleys to a maze. The essence of the maze remains the same but the maze gets larger, more difficult, and takes longer to traverse. The only way to recover that lost performance is to clean and compact (defrag) the registry files. (Of course, a complete reinstall of the OS will do the same thing but that is what we are trying to avoid.)

The very thought of working with the registry is enough to give many users something approximating to a heart attack. It is not, however, the hazard it might appear at first glance. If a backup copy of the registry is made before any changes, mistakes can be reversed. Making a registry backup in Windows ME or Windows XP is simply a matter of creating a restore point before making any changes. In older window versions it is necessary to use the registry editor to export the registry to a .reg file. The registry is restored from the command line using the scanreg program. This procedure is not difficult but is beyond the scope of this article. Be sure you familiarize yourself with the procedure for your operating system and make a registry backup for safety's sake. In fact, however, mistakes requiring restoration of the registry from a backup are not likely if a dedicated registry cleaning program is used. These programs make a backup of the items they delete so they can be restored from the program. Up to now (fingers and toes crossed) I have never had to use either one.

There are many commercial programs for cleaning the registry. Most of these programs seem no more effective than free ones and usually include many other functions which you may or may not need. Some of them offer features such as deleting obsolete, orphan, or duplicate DLL's which I consider dangerous, even for so called power users. If you have one of these programs, I suggest learning just what it does and using it judiciously. I would not recommend buying such a program just for a registry cleaner.

All registry cleaning programs do (free ones also) is locate invalid entries and mark them for deletion. You can decide whether to delete them in mass or to selectively choose those to be deleted. In general all entries which go nowhere (broken links), are marked obsolete, or are associated with programs no longer installed should be deleted.

I use a program called RegSeeker (Version 1.35). It appears to be the equivalent of any of the commercial products and does not include options I consider inherently dangerous. It is supposed to be functional with all version of windows from Win95 up. I have only tested it on Win XP however. I cannot guarantee its performance on the other versions. It is free for personal use.

RegSeeker comes in a zip format. It does not need to be installed. Create a folder wherever you want (in Program Files is always a good choice) and unzip the file in it. RIGHT click on RegSeeker.exe and drag it to wherever you want a shortcut to appear. Release the button and select "Create Shortcuts Here". Double click on the shortcut to run the program.
The opening screen will list several functions available that you may find useful at some later date. The one we are interested in is "Clean The Registry". Click on it. On the right hand side of the program window you will be shown a list of the registry keys that will be checked. I suggest that HKEY_CLASSES_ROOT be unchecked. (There will always be many unused extensions found but I think it best to leave them alone. Extensions are at the heart of the operating system and, in my opinion, best left in their original state.) Click on the OK button and RegSeeker will check the registry. Delete the items found (all or selectively as you choose).

You've now completed the task except for defragging the registry. At one time I would have said that empty space in the registry would not effect performance. Experience has taught me otherwise. There is a perceptible performance improvement after defragging.

PageDefrag (version 2.21) (Online Editor's Note: To download this freeware, visit the SysInternals web site and download the version appropriate for your operating system.) l defrag the page file and swap files in windows XP. (I do not know of any equivalent program for older versions of windows.) Like RegSeeker, PageDefrag comes in zip format and requires no installation. Unzip it in a folder and create a shortcut to pagedfg.exe. Double click the shortcut to open the program window. It will show the files that will be defragged and the number of fragments in each. Even if they show no fragmentation (1), Check the defrag on next boot (blank space will not show as fragmentation) and then reboot the machine.

After rebooting you should perceive a considerable increase in performance. If not there is always the complete reinstall option. If you choose to use the programs I have referenced, use Google to find a current site for downloading the programs.
CAG