In the first two parts of this article series we talked about free antivirus utilities overall and PC Magazine’s top choices in the free antivirus software utilities. In the second article we discussed CNET’s recommended and most popular antivirus utilities. In this third and last article of the series, we will offer you a list of the most popular free utilities for PC maintenance and optimization. These tools will help you keep your PC clean while providing you the means of removing registry errors, unwanted programs, manage internet and system start-up applications and extensions. For the PC user that wants a few extra free software toys to work with in order to maintain a well-ordered PC and to, possibly, squeeze a bit more performance out of your system here are some of my favorites as well as popular with CNET and PC Magazine.
1. CCleaner by Piriform, has been downloaded over 105.6 million times via CNET; and is considered the number one maintenance and optimization utility by CNET and yours truly (this author). I’ve personally used (and still do) this program for over a decade since its first unveiling. Every PC I’ve purchased over the past decade (Initial release September 23, 2003).
CCleaner is a freeware system optimization, privacy and cleaning tool. It removes unused files from your system allowing Windows to run faster and freeing up valuable hard disk space. It also cleans traces of your online activities such as your Internet history. Additionally it contains a fully featured registry cleaner.
What's in the box you ask: Tools for clearing your temporary files, cleaning the Registry, tools to remove unwanted programs and files, duplicate file search tool, tools to manage/delete startup applications and extensions in multiple browsers, removes unused cookies from your browser, Microsoft Edge (Spartan / IE 12) cleaning, Google Chrome Internet Cache and Session cleaning, Firefox Web Apps start-up management, Windows 10 (yes even Win10 already) Recycle Bin and Delayed cleaning support, Skip UAC functionality for domain accounts and Adobe Reader DC cleaning and it supports 64-bit systems.
Downside: As with all utilities that can alter the registry, delete programs and affect changes to the start-up of the PC, be careful and know what you are changing or deleting. Mistakes can be costly if you make changes before backing up your files.
2. Malwarebytes Anti-Malware (Windows) is another program I automatically add to ever PC I buy. As freeware utilities go, this program is probably the best free anti-malware program available. CNET total downloads to date are 134.2 million users. Malwarebytes Anti-Malware is a well-established malware-killer. The latest version includes a built-in anti-rootkit, access manager, automatic scheduler, exclusion options, and other utilities under the settings tab. Anti-Malware 2.0 looks for out-of-date versions before it starts every scan in order to make sure the most current version and malware database are available for your system during the scan. Malwarebytes' Chameleon technology helps stop stubborn malware from blocking Malwarebytes Anti-Malware from running.
Downside: If you want the extra features that are only found in the subscription version – there is an annual subscription fee. Just keep in mind that even if you buy the subscription version for even one year, your copy will revert to the free version after the expiration date and can always upgraded at a future date.
3. Advanced SystemCare Free (mentioned in the previous article on this topic) has been downloaded over 124.3 million times via CNET. This is a CNET #1 in the category of comprehensive diagnostic software. Advanced SystemCare Free includes a system cleaner, optimizer, uninstaller, boot-boosting, browser-protecting startup manager, a Toolbox, turbo boost, performance monitor widget, and other upgrades. It includes Homepage Protection, System Reinforce, and Surfing Protection, in addition to malware, spyware, and junk file cleaners. A real plus is its one-click scans for Fast, deep cleaning, and single-click performance as well as internet and security boosting. On the downside, some useful tools and features in Advanced SystemCare 8's menus aren't available in the free version.
4. Wise Registry Cleaner is an excellent free Diagnostic Software program with over 8.8 million downloads on CNET. Wise Registry Cleaner scours your Windows Registry for invalid entries and system-slowing junk. It's safe, easy to use, and (best of all) free. The no-nonsense layout groups all the features you need right where you need them, including Registry Cleaner with Normal, Safe, and Deep Scan modes, a System Tune-up, Registry Defrag, and Scheduler tools. Caution: it can delete registry entries that should be kept if you are not paying attention; make sure you know what you are deleting. It requires a reboot for the changes to take affect and if you delete a registry entry erroneously, you’ll find out the hard-way after reboot; in other words, something may not work as it should.
5. Wise Care 365 Free, a powerhouse PC Cleaner, Maintenance and Optimization program with over 4.8 million downloads from CNET. This all-around utility to optimize and maintain your PC's performance groups its primary utilities into sensible categories like System Cleaner, System Tune-up, Privacy Protector, and PC Checkup. It is primarily designed for Windows XP so it may not be usable on Windows 8/8.1.
6. SlimCleaner Free (Maintenance and Optimization Program) has been downloaded over 2.7 million times. SlimCleaner is a lightweight program for removing all kinds of junk and broken files from your PC. Even inexperienced users will quickly get comfortable with this program's straightforward interface, and the combination of features included means you'll have all tools you want at your disposal at any time. You can perform quick scans and clean-out broken files and other issues just like in most like-type utilities. There is also an option for automatic cleaning. It combines scanning and cleaning however you sacrifice the opportunity to review the scan results before they are deleted. The utility also includes optimization tools, startup manager, disk tools, Windows tools, and other options for optimizing a PC and its browsing performance. On the downside, the defrag function doesn’t seem to do much; but as long as you are happy with Windows’ defrag function, the SlimCleaner shortfall isn’t an issue in the long run.
7. IObit Malware Fighter (Windows) has been downloaded, according to CNET, over16.2 million times. IObit's latest version looks and functions like Windows 8. The standard options are there to scan, protect and update; the Action Center provides for additional options. This program has malware and a spyware removal utility that detects and removes deep infections, protects your PC from various potential spyware, adware, Trojans, keyloggers, bots, worms, and hijackers. It has real-time protection that includes internal apps called: "Startup Guard", "Browser Guard", "Network Guard", "File Guard", "Cookie Guard", "Process Guard", "USD Disk Guard" and "Malicious Action Guard." This application uses cloud scanning. The newer 2.0 version is touch screen friendly. Although this version is free, it is ad supported; thus, you can expect some unwanted ad downloads you might need to manually remove.
8. Auslogics Registry Cleaner (Windows) has been around for a long time and has been downloaded over 1.8 million times according to CNET. It’s not a robust tool; it’s fairly basic, providing just what is needed to keep your PC error free. When you first open the utility you can chose to Scan immediately and it will display the scan results for you to review before taking action to fix or ignore the item shown. Scans are quick; results grouped by categories and expandable. If you’re not interested in scouring through the results to evaluate each one on your own, you can always select the Scan and Repair option; this will auto-fix errors it deems necessary. Downside: The “Help” document is woefully lacking. Don’t expect to get any help interpreting the application and its results unless you can find an online forum somewhere to seek your answers.
9. Wise Registry Cleaner Portable has been downloaded via CNET over 179,000 times. This utility cleans, defragments, and optimizes the Windows Registry. As with most registry utilities it can create backups and run scans at scheduled times. You’ll want to run a system cleaner first before each registry scan/repair. Wise Disk Cleaner is another free app that works well with its sister software, Wise Registry Cleaner; however, it is packaged separately. Some users may want to use CCleaner for scrubbing the junk out of your system and use Wise Registry Cleaner for the defragment/optimization capabilities. You can also use the Windows scan and clean utility prior to running Wise Registry Cleaner. Remember to back-up your registry before defragging and optimizing it: you never know when thing scan go wrong. The help documentation is weak – actually a bit garbled and incoherent. The online help and user's manual, on the other hand, are decent and answer most user questions.
10. Comodo System-Cleaner (Free) with over 169,500 downloads via CNET is the final utility on our list. The Comodo System Cleaner combines three utilities: Registry Cleaner, Disk Cleaner and a Privacy Cleaner. Running these utilities will help rid your PC of duplicate, harmful, or otherwise unnecessary files. This utility will automatically create a backup of the registry before it begins cleaning your system; thus avoiding accidental data loss. CNET tests demonstrated that the Comodo suite performs each process swiftly and efficiently. In a few cases, Comodo identified and cleaned junk files other utilities missed. However, CNET suggest not running this Comodo program in lieu of your primary antivirus and spyware program; use it as a secondary cleaner. 
There are many great free programs available to help you keep your PC clean and secure. We are not suggesting that the paid and paid-premium programs are not worth the money; paid subscription security programs usually have multiple tools that work in concert to provide instant updated security information, often hands-free system security that automatically checks, blocks and cleans your PC without you having to lift a finger. All too often the free versions are packaged with advertisements by sponsors of the freeware. These ads are difficult, sometimes impossible, to remove once they’ve embedded themselves in your system; and the freeware protects the ads so that it is difficult or impossible to remove them. The paid programs are normally devoid of any sponsor ads; of course, the creator of the software embeds their company’s suggested upgrade features (at a cost) in the system; but that is to be expected.
If you are willing and able to personally manage the security of your PC by actively and regularly perform antivirus scan, anti-malware scans, registry cleaning, removal of unwanted programs etc., freeware programs will meet your needs. Even those of us that have full paid subscriptions to security suite utilities use some of these freeware tools as supplemental programs helping us target specific areas of our PC security. My favorite additions to my Webroot Security Suite are CCleaner and Malwarebytes Anti-Malware. You need to look at what you want to do and how much effort you want to make in digging-in and tweaking your system. At the least ensure you have an antivirus and a firewall utility integrated in your PC.