Guest column: Windows registry wrapup ... really

Over the past couple of weeks we've discussed some of the architectural and operational aspects of the Microsoft's Windows 98 and NT registries. To wrap up this tour of technical tomfoolery, this diversion into digital detail, this ... [enough already! Ed.], we're going to cover a few tools that make working with registries easier (easy would be nice, but it is just not possible -- hey, it's Windows, what did you expect?).

A couple of missives ago we mentioned that backup copies of the registry are kept in various odd places.

Well, Gearhead just found out about one that seems to be mainly unknown. In fact, despite all who wrote in regarding the topic of registries, only two readers - Alan Striegel and John Secondino - brought this particular cranny to light. That cranny is a utility included in Windows 98 by Microsoft called scanregw.exe.

Scanregw.exe can be found in the c:\windows subdirectory and is automatically run once every day at boot up. Note that this means that if you don't boot up once per day, backups will be skipped.

By default, scanregw.exe makes copies of system.dat, system.ini, user. dat and win.ini in a .CAB archive file in c:\windows\sysbckup. Also by default, scanregw.exe keeps the past five days' versions of the backup named RB000. CAB through RB004.CAB.

If you desire to keep more versions than the default, find the file scanreg.ini in c:\windows and locate the MaxBackupCopies entry and change it to whatever value you please. Just remember that each copy will be the same size as the current registry, so you may chew up a lot of disk space if you set this parameter high.

Note that scanregw.exe does more than just back up the registry files. It automatically optimises the registry and, as you might have noticed earlier, backs up system.ini and win.ini. It can also back up other system files (see the comments in scanreg.ini for details).

If you are about to make changes to the registry and want the truly latest version just in case, you can run scanregw.exe yourself. Scanregw.exe will do its thing and then ask you to confirm that a new copy is to be saved.

Gearhead knows this is more excitement than you can stand, but hold on - there's more! There's also a DOS version called scanreg.exe. It does several things differently from the Windows version, including restoring the registry. Why doesn't the Windows version do this? Gearhead has no idea, but the thought of Microsoft programmers suffering from too little sleep sounds plausible.

When you run scanreg.exe from a command line you can add parameters: for example, /backup backs up the registry, /restore restores it, /fix repairs errors, and /scanonly only scans the registry and reports on problems but doesn't fix them.

If you want to manage registries on a network rather than on a single-machine basis, Mark Self of KVLabs, Inc. wrote to tell Gearhead about his company's tool called KVManager. This server-based utility has a Web interface that lets you manage lockdown, rollback, monitoring and change management of the registry settings of multiple networked machines running the company's client-side software, KVAgent. If you've tried this software, let me know what you think.

Also worth noting is KVLabs' registry information site,, and its searchable database of some 1,400 registry settings at http://

The company makes a small part of this database available for free and, much to my irritation, doesn't tell you how much it costs for a subscription, a practice that Gearhead finds unbelievably irritating.

Thanks to everyone who wrote in, the various Windows registry discussions seem to have struck a chord. . . . Oh, and for reader Bill Hawk: Did the discussion of "hives" under NT answer your question?

Next week, we'll start on brain surgery and rocket science. Keys, subkeys and hives to

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