Problem with CCleaner - September 2017

Nope Carol, most of the long-term MVP and other members here have been recommending against the use of any registry cleaner including CCleaner since at least the point at which Microsoft shifted their own official stance, pulling the Windows Live OneCare registry cleaner that was once part of the online safety scanner.

This occurred at roughly the time the OneCare antivirus stopped being sold in 2008, though many of us here had been recommending against using registry cleaners for quite a while before that.

The best article I've found that covers this evolution, referencing both the history at Microsoft and the reasons for the change itself, which have to do with changes in the design and operation of the registry since the release of Windows Vista, is the following.

Microsoft does not support use of Registry Cleaners in Windows

So those still holding onto the long past legacy of registry cleaners are actually acting in direct opposition to what Microsoft recommends, no matter what they choose to believe.  Typically this is due to the fact that they really have no understanding what a registry cleaner does and doesn't do, especially as relates to the lack of ability to determine whether or not removing something might in truth be damaging to the registry and so the entire operating system.

The problem is that there are no simple standards of what should or shouldn't be removed, since that's typically decided by those designing the original program.  So the commonly held belief that any program not currently installed should have everything relating to it removed is actually wrong, since in some cases these legacy keys are required in order to keep that portion of the registry stable.

For this reason it's necessary for the person operating a registry cleaner to fully understand the ramifications of the registry changes they are about to make, which with a moments thought is easy to realize can't be true, since only the original application creator truly knows this for certain.  This is the basic flaw that makes all registry cleaning inherently dangerous and precisely why Microsoft itself dropped the Windows Live OneCare registry cleaning module.

A great example is the existence of "First Run" selections within the Office application suite and in fact many programs using the Microsoft Installer, since this type of key is inherently designed to look like an orphaned entry within the registry.  The first time I ever tried CCleaner myself many years ago I immediately realized it had mistaken many of these keys within my partially installed Office package, which if I'd allowed it to remove these would have broken their designed ability to prompt for the original installation CD if an attempt was made to open that particular program feature.  Instead I immediately uninstalled the actual dangerous program, CCleaner.

If you can't understand what I'm explaining, you're indicating to those here who do precisely why we are so clearly against the use of all registry cleaners.  Only those with a deep knowledge of the registry and the individual applications that use it are really capable of making such decisions, but you'll actually find that most of these skilled individuals have stopped using them themselves for this very reason, instead choosing to manually peruse the registry for the specific keys needing to be changed on the rare occasion this might be necessary.

Once the registry cleaning feature is removed from CCleaner, it basically becomes a glorified file cleaner, which since a well behaved system does much of this itself today, is also unnecessary.  Whatever the built-in Windows functions don't already do themselves are typically better off done with simple targeted tools designed to remove only well known temporary files for example, rather than a general purpose "cleaner" that tries to perform multiple functions some of which have always required a technically skilled person rather than the typical uninformed consumer PC owner.

Rob

"Windows Defender AV detects the backdoor in compromised CCleaner versions as Backdoor:Win32/Floxif.gen!A; update to the latest version"

https://twitter.com/msftmmpc/status/910270933608181762

Image source: http://www.majorgeeks.com/news/story/ccleaner_hacked_malware_spread_to_2_2_million_users.html

Backdoor:Win32/Floxif.gen!A

https://www.microsoft.com/en-us/wdsi/threats/malware-encyclopedia-description?Name=Backdoor:Win32/Floxif.gen!A

Also see updated bleepingcomputer.com post.

Avast Clarifies Details Surrounding CCleaner Malware Incident

https://www.bleepingcomputer.com/news/security/avast-clarifies-details-surrounding-ccleaner-malware-incident/

In addition with regard to using CCleaner I think the following recent article provides a fair assessment.

What Does CCleaner Do, and Should You Use It?

https://www.howtogeek.com/172820/beginner-geek-what-does-ccleaner-do-and-should-you-use-it/

Note: If you don't use an ad-blocker, please ignore third-party advertisements.

~bhringer

Ads for questionable 3rd-party utilities are one of the many reasons we've been recommending against registry cleaning, optimization and other such tools for around 10 years now, since most of these are not reputable and the tiny handful that may be provide so little of value that they're not worth the potential risk.

In most cases the Microsoft built-in utilities provide everything that the typical consumer requires.  Since the Disk Cleanup utility provides individual selections for all items that Microsoft considers safe and necessary to remove, I'd rather use that then a 3rd-party tool that intentionally rips out items that were never intended to be.

Though it's possible to use the task scheduler to schedule a disk cleanup operation, I've personally seen so few temporary file remnants left behind recently that I rarely even bother to use the tool any longer.

Since there are settings within the Internet Explorer and Edge browsers that allow for Temporary Internet files to either be limited in size and/or automatically emptied on exit from the browser, I've found these to be far more useful than any manual deletion tool.

Temporary files left by malware are typically found in the browser cache files automatically removed on proper exit from the browser, so these are of no true concern.  If malware has already succeeded in infecting a system then the location of these files isn't important, since the protection has already failed.  With the browser and other security settings I use along with Windows Defender, neither my Windows 8.1 or 10 systems have ever been successfully infected, so temporary files are incidental and unimportant.

There hasn't been a good reason to delete cookies in years, since the advanced browser settings controlling these provide the ability to block or prompt, which is a far better way to manage cookies, since they perform their activities during a browsing session.  Once the session is exited the privacy issues cookies can create have already been completed, so it's too late to have any useful impact.

If I'm a Microsoft fanboy for using its products and stating so, then what are you when you argue for a 3rd-party product like CCleaner?

Rob

Thanks for the info. re CCleaner Malware Incident. Microsoft may not recommend the use of programs that include a registry cleaner, but that's not likely to stop the rest of us from recommending CCleaner. ;-)  DYK, they included a registry cleaner in Win95 called RegClean?

CCleaner is a very popular, highly recommended program. It's not comparable to some of those questionable Windows repair, fix-it type apps. FWIW, CCleaner's registry cleaning tool is far from aggressive and is actually very safe to use, though unnecessary.

As for it may intefere with Windows Defender, you failed to mention you can just uncheck Defender under Applications section.

Edit: It'd be good to change the title of your post, imo, since the problem isn't with CCleaner in general. It's in reference to downloads between specific dates.

Information was put in my initial post for anyone who wants to read it. 

The articles/links referenced in the initial post are self explanatory and easy for most people to read and comprehend.  So I’m not going to explain what most folks are capable of reading and understanding.

Since I'm in my 70's I'm well aware of Win 95.  For some reason MS became concerned about registry cleaning programs and tuneup utilities and they quit including it in their programs (and stopped recommending such) before OneCare was phased out in 2009.  I never asked why. 

You or any other computer user can use or recommend CCleaner, speed optimizers, registry cleaners, driver update programs, McAfee or anything you want to as far as I'm concerned.  

And if the forum owners don't like the title of the original post in this Discussion I'm sure they'll change it when they read this thread.

Have a nice day...

Thanks for the info. re CCleaner Malware Incident. Microsoft may not recommend the use of programs that include a registry cleaner, but that's not likely to stop the rest of us from recommending CCleaner. ;-)  DYK, they included a registry cleaner in Win95 called RegClean?

CCleaner is a very popular, highly recommended program. It's not comparable to some of those questionable Windows repair, fix-it type apps.

As for it may intefere with Windows Defender, you failed to mention you can just uncheck Defender under Applications section.

Edit: It'd be good to change the title of your post, imo, since the problem isn't with CCleaner in general. It's in reference to downloads between specific dates.

Edit: Removed info re CCleaner's reg cleaning tool, so as not to cause issues...