"Before using any registry cleaner, I highly recommend that you create a System Restore restore point, and even better, do a full registry backup with the ERUNT utility. In some cases, aggressive registry cleaning can remove entries required for some programs to operate.
I should mention that technology experts have differing opinions on the value of registry cleaners. Some adamantly claim that they cannot possibly improve system performance. Others say they might help a little, but point out that in some cases they can cause damage as well. And of course others believe they can offer significant benefits. I tend to be in the latter camp, but recommend caution when using a registry cleaner. Choose the tool that suits your level of technical expertise, and do your preparatory backups."

http://askbobrankin.com/do_i_need_a_registry_cleaner.html

I never recommend them. Much better off Managing your start up programs, clearing out history, temp files, and a Defrag.

I have yet to have EasyCleaner from ToniArts wreck anything on a clean system, and it can find a lot of references to removed software. There are other more aggressive cleaners out there like Eusing, which does a great job also, but use at your own risk. Measurable improvement? I really couldn't say for sure.
Backups prior - strongly advised.

on many of the security support forums you will find the same response about registry cleaners; do not use them.
That is always my advice also. yes some may be better some may make backups some may claim to remove thousands of problems, but unless you want to take the chance of what a bad registry cleaner can do then just step away from them.
In these later versions of windows from xp forward they are not needed. So unless you are an advanced user with some specialty in the registry just don't use them.
There are so many bad programs out there the chance of hitting a good one among them is not worth the risk since there really is no good reason to use one in the first place.
A very good article by Ed Bott on the subject
Why I donÂt use registry cleaners
and from Bill P creator of winpatrol
"Bits from Bill"
and one of the support forums
Registry Cleaners, not recommended

Equal time, if you plug in "why you need a registry cleaner" in your favorite search engine, and filter out the usual misinformation and sales pitches, there are some valid points, as anyone who used "Clean Sweep" ages ago can attest. Sadly not all software cleans up after itself on an uninstall, and random obsolete activex references are unwelcome on machines I service.

That's why I use Revo Uninstall to uninstall programs rather than the program uninstall or using Control Panel. It does a good job of cleaning up random registry entries and program files left behind.

But...having said that...isn't then Revo a form of registry cleaner right there above and beyond the base Windows uninstall?
Hey, catch-22, boils down to "use what works you"!

I have used CCleaner since 4/2007. I use it on 2 machines and I have not had a problem that I could knowingly blame on it. I always backup the registry before I use it. This is not a recommendation-just my personal experience. As with all such-use with caution.

There are various levels of achievement and knowledge here on the forum. It is my belief through years of observation and participation the vast majority of the members here are newbie to intermediate level. To openly encourage the use of registry utilities or in any way down play the potential negative results of their use without any disclaimers or warnings is to say the least irresponsible.

DA

I agree it would be irresponsible to insist everyone simply go ahead and blindly run a cleaner, but the responses were in general, I think at least, simply answering the original post. Also there were cautionary notes about backing things up first and use at your own risk. I would deem that responsible, but that's just my take.

Goldy,
I like Ccleaner and Comodo. I've used them for about 4 years without problem.

Advanced System Care (free version) at Microsoft also does some registry clean-up. Very safe.

Advanced system care is NOT by microsoft, it is by iobit and I personally would never use their products since they were involved in stealing from malwarebytes. They are a China based company and apparently have different ideas of what is allowed. Not a product I would recommend.

I've used CCleaner and always let it save before cleaning the registry. I leave it at the default setting and have never had a problem. I use it at least once a month on 5 machines.

Jane

It is an outstanding protocol to save before removing using CC. However, I do wonder how many users are not armed with the knowledge of how to restore the removed material. Hence another thread, "How do I.....".

RC is correct about ASC, and it is a much more powerful and deeper cleaning utility than CC. It is without a doubt an application to avoid for the newbie and inexperienced; just like other registry utilities.

And yes, CC is NOT full proof. IT can cause concerns. Like anything it is not perfect. The current version reports my Quicken file pointers to lack association and unnecessary. Can you imagine what would happen if I allowed CC to remove the entries? No Quicken access.

DA

Raven,

My goof! What is the one by Microsoft that disables Windows Defender and replaces it?

Iris you probably mean Microsoft Security Essentials

Thanks Owbist!

dumb dora