how to clean registry ?



Hi to all,

I have a lot of trash in my registry left behind from years of uninstalls
which I think is slowing my system (Win2000 + P4 2.4mh chip) and causing
some problems. Is there some way I can clean my registry out without
corrupting everything else ?

I've manually removed things I know are long gone without problems, but I
don't dare attempt removing any more and I don't want to reformat and

Thanks to all, Rob

Bob I

That may have been an issue with the DOS versions of Windows. With NT
only fix what's broken. If there is a specific problem the folks here
can help you with it.

Jim Byrd

Hi Promicro - In my experience all of these Reg cleaners, even the best, are
fraught with danger. I advise against using them except in one specific
instance, that is when you have one that is capable of doing specific Reg
searches, and you NEED (not just WANT) to remove the remaining traces of
something that didn't get uninstalled correctly. (and you didn't have
foresight enough to install it using Total Uninstall, or direct dwnld here:, in the first
place.) (As an aside, there are, however, some third party Registry Editors
which can be of great help with both the incorrect uninstall and with
certain malware problems, especially some of theCoolWebSearch types such as
the AppInit_DLLs variant of the about:blank version of CWS, for example. I
can recommend Registrar Lite, here: .)

There are a couple of specific bugs that can cause abnormal growth in either
the System or Software hives; however, they are rare, and unless these hives
in %SystemRoot%\System32\config are very, very large (in the hundreds of
megabytes), then I would council you to leave your Registry alone except for
the special circumstances I mentioned above.

I and most other MVP's that I know believe that Registry modifications of
any type are probably best done manually, very carefully, with a thorough
knowledge of what's installed on your machine, and what you're doing, and
then only when necessary. There's very little (if any!) noticeable benefit
in either space saving or speed achievable by cleaning out the Registry
except in those few cases where there's a specific problem the client is
experiencing (usually uninstall or malware related in my experience) that
needs to be fixed.

Lastly, if you must screw around with your Registry, then at least get
Erunt/Erdnt, and run it before you do the Reg clean. You'll then have a
true restore available to you. Read below to see why you might not just
using the Reg cleaner's restore:

Get Erunt here for all NT-based computers including XP: I've set it up to
take a scheduled backup each night at 12:01AM on a weekly round-robin basis,
and a Monthly on the 1st of each month. See here for how to set that up:, and for some
useful information about this subject.

This program is one of the best things around - saved my butt on many
occasions, and will also run very nicely from a DOS prompt (in case you've
done something that won't let you boot any more and need to revert to a
previous Registry) IF you're FAT32 OR have a DOS startup disk with NTFS
write drivers in an NTFS system. (There is also a way using the Recovery
Console to get back to being "bootable" even without separate DOS write NTFS
drivers, after which you can do a "normal" Erdnt restore.) (BTW, it also
includes a Registry defragger program). Free, and very, very highly

FYI, quoting from the above document:

"Note: The "Export registry" function in Regedit is USELESS (!) to make a
complete backup of the registry. Neither does it export the whole registry
(for example, no information from the "SECURITY" hive is saved), nor can the
exported file be used later to replace the current registry with the old
one. Instead, if you re-import the file, it is merged with the current
registry, leaving you with an absolute mess of old and new registry keys.

Please respond in the same thread.
Regards, Jim Byrd, MS-MVP


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