Registry Cleaners - Good or harmful to your PC?

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It is only natural that we all want our PCs to be in good working order, improved system performance, so that is exactly how programs are advertised to entice. They say things like:

           •      PC crashes? Get registry cleaner to repair it!
           •      Fix registry errors!
           •      Improve PC performance!
           •      Have your computer running like new!

These might sound really good but are not necessarily true. The scanners don't always deliver what they claim to do, at times quite the opposite.  I have seen reports where after using a reg cleaner the user could no longer open any files, Control Panel buttons are missing, browser is broken, errors pop up, and in some cases the system can no longer boot!

Despite that, in the Virus & Spyware zone I sometimes see posts suggesting a registry cleaner to fix PC crashes and registry errors, and techs/"experts" recommending the use of a registry cleaner as part of their virus cleanup routine.

Using a registry cleaner might be okay for an advanced user who knows exactly what he is doing. But for an inexperienced user who just like to scan and click the "Fix all" button without making sure that those entries being deleted are really redundant can have a disastrous result.

The risk of removing a critical entry is greater than the benefits you hoped to gain when using one of these tools. If you are not careful, a registry cleaner can mess up your registry big time, and a messed up registry is a broken Windows.  A registry cleaner has the potential to make your PC unbootable.

Is it necessary to clean the registry?

In my opinion, no. It is not necessary to clean the registry because a system with a bloated registry will perform just fine, and cleaning it will not make much difference in performance speed.  I have used Registry Mechanic, JV16 Tools and TuneUp Utilities until I started noticing that I was having more problems than ever before. When I started checking, these tools were actually reporting redundant entries of programs that are still installed in the system, so that was the end of using these tools for me (if you are an advanced user, it is better to remove those redundant entries manually yourself, at least then you know exactly what entries you are removing. Otherwise, leave them alone).

Apart from that, any redundant entries there won't do any harm and cleaning the registry will NOT make your PC faster. In fact, you could be doing your registry a disservice by deleting those redundant entries because the registry will become fragmented. You should also know that searching in a fragmented database slows down your search.

Don't take my word for it, read what Mark Russinovich(Co-Author/Founder of Winternals and Sysinternals) wrote about registry cleaners.

In his blog, when Mark Russinovich was Asked:

"Hi Mark, do you really think that Registry junk left by uninstalled programs could severely slow down the computer? I would like to 'hear' your opinion."

He wrote:

"No, even if the registry was massively bloated there would be little impact on the performance of anything other than exhaustive searches....”
“...I haven't and never will implement a Registry cleaner since it's of little practical use on anything other than Win2K terminal servers and developing one that's both safe and effective requires a huge amount of application-specific knowledge."

Based upon the numerous reports, testimonies and personal experience, in my opinion, a registry cleaner is of little practical use but the risk it poses is too big to be ignored. Cleaning the registry will have no effect on your system's performance, yet, there is a very good chance it will make your system unreliable.
So next time you use a registry cleaner, make sure to doublecheck those entries before deleting them, or think about whether it's even worth the risk in the first place.

I hope you find this article helpful.
LVL 38

Expert Comment

Great stuff, got my Yes vote.

I learned a while back (the hard way) not to let anyone/thing but me touch the registry.
LVL 65

Expert Comment

by:☠ MASQ ☠
Thanks for this, hope the contents are taken on board by everyone who reads it. There is no such thing as an intelligent registry cleaner.
LVL 47

Author Comment

That's right, not one intelligent reg scanner out there.

Thanks guys for the "Yes" votes :)
I shared this link on my Facebook wall  8 hours ago but not a single click on the "Like" button :(.
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LVL 73

Expert Comment

Cannot agree more to any point made!
LVL 38

Expert Comment

Excellent article - we need to refer a lot of our members to this information - to off-set the bad advice that gets posted.

Thank you for writing it.
Big 'Yes' vote above.
LVL 10

Expert Comment

I didn't realize this article was here or I would have linked to it every time some one suggests using a "Registry Cleaner".  I will now, and my opinion EXACTLY mirrors yours about the necessity to clean the registry.  Been there, done that and wouldn't want any one else to expose themselves to the immense amount of grief those so called "Tools" can cause in the wrong hands.

You can't Goggle anything error related these days without getting hits on Reg Cleaners.  I'm sure they run scripts that look for searches on errors and run subsequent scripts that display "Fix <insert searched error here> with a Free download of our  <insert error here linked to "tool">.  The hits they get from people looking at their site probably pays their server bill from the advertising revenue.

If there's one person that knows what he's talking about, it's Mark Russinovich.  I believe he is one of the most respected people in the industry and anyone would be foolish not to heed his advice.  I did not know of the quote in his blog you linked to.  Thank you for that.
LVL 47

Author Comment

Qlemo, younghv, Jim-R:

Thank you so much for your comments. Hopefully, anyone who reads this article will also find it helpful.

"If there's one person that knows what he's talking about, it's Mark Russinovich.  I believe he is one of the most respected people in the industry and anyone would be foolish not to heed his advice."

Exactly, well stated.
Thanks for your input, much appreciated.

Expert Comment

Yes...registry cleaners are practically useless for general purpose use..but sometimes when u wrongly install an application...it would be necessary to clean up the registry and perform a clean install,I personally have experienced this.So I would say that the registry is a very complicated place and modifying it without proper knowledge is highly not recommended even with registry cleaners.Thanks for this excellent article.
LVL 39

Expert Comment

Excellent article.  I couldn't agree more.  I personally HATE the very expression "registry CLEANER" and the manner in which all kinds of hotch-potch programs are advertised just as you described, ie. "improve performance", "make your PC run like new".

Leftover registry keys and values are not "dirty", and therefore don't need to be "cleaned".  I suppose an analogy would be whether random paper litter fluttering about on a sidewalk actually slows down your walk from the bus stop to work.  To those who care about it the litter's presence is really annoying, but you certainly doesn't impede your journey and you aren't going to trip and stumble over it.  Cleaning the chewing gum, cigarette butts, and dog crap off the sidewalk with a jetwash won't get you to work any faster, although it will probably keep your shoes shinier for longer if you are the type who has his nose buried deeply in Facebook on a mobile and don't watch what you're walking on and in.

It always amazes me how many of the people who are suckered into the scary "security-related" temp-file results of an all-purpose "cleaner and optimizer" program are the same ones who think nothing of littering Social Networking sites with highly personal information that stays there.

Used with the appropriate skills and understanding it is far better to use a handful of bespoke utilities separately in "diagnostic" mode to track down very specific issues that are causing problems, and then find or research the "fix".

Excellent article and solid advice.

Expert Comment

I am with "madhusudhan000". I work in one of the worlds largest networking environment comprising of over 150,000 systems spanning across the world. With connections ranging from wireless to wired and though using full tunnel and split tunnel access. I also support several thousands of applications. I contribute to over 50% of resolves require us to dive into the registry. Yes the advertised registry cleaners are useless, but there are a few. I primarily hand edit the registry. So cleaning the registry from time to time has to been done or it causes network connectivity issues, log-on issues, certificate issues, and the list goes on.
LVL 50

Expert Comment

Thx for the article, very informative. I have added "registry cleaners" to the dont do list


LVL 75
I use CCleaner, but ... I don't have anything in the 'Registry' section checked.  It does a great job of house cleaning a lot of other junk - all at one time.


Expert Comment

Yep, registry cleaners are bad in the wrong hands, and not very useful even in the right hands.

I use the advice from Jerry Honeycut: Backup first, change later. (always)

Any modification to the registry is potentially dangerous, and should be handled with care.
LVL 47

Author Comment

I still use CCleaner now and then but just for cleaning temp files not for cleaning my registry.

Also if your PC is infected make sure you don't run CCleaner(or any temp folder cleaners) just yet in case one of those rogues that move files to the temp folders is present in the system.

Windows XP/Vista Recovery - Desktop icons missing - Empty Programs files

Thank you guys for your comments and input.
LVL 38

Expert Comment

+1 for the Russinovich reference :)

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