The Tools And How They Did
I'll provide more detail on the individual tools as we go along, but the list includes JV16 PowerTools version 184.108.40.206 (the last free version of this venerable tool, considered by many to be the best free Registry cleaner ever offered); JV16 PowerTools 2005 (the current, commercial version of the classic tool); Registry Mechanic from PCtools.com; ToniArt's EasyCleaner; StompSoft's Registry Repair; Rose City's Registry First Aid; Iomatic's RegistryMedic; EasyDesk's Registry Drill; RegistryFix's eponymous RegistryFix; and Registry Cleaner from CleanMyPC. In each case, I downloaded the latest available version of each tool just prior to testing.
There are, of course, many, many other Registry-cleaning tools available. My choice of 10 is not meant to be definitive, but rather merely representative of what's available in this class of tool. If you have additional information on other tools of this type, by all means tell us: Use the link at the end of this article to post your information in the associated discussion forum.
Now, let's see what they did:
# JV16 PowerTools 220.127.116.11: I included the last free version of this highly regarded tool -- from 2003 -- because so many of you will be familiar with it. As such, it can be a kind of touchstone you can use for context in comparing newer tools. When run on my test system, it identified 307 problematic items in the Registry, 122 of which it deemed "safe to remove." (The other items might or might not have been safe to remove, but JV16 PowerTools properly errs on the side of caution. This helps prevent over-aggressive Registry cleaning, which can lead to new problems.) Let's remember the 122 "safe to remove" items as a crude benchmark against which to measure other, new tools: surely any newer tool worth its salt should be able to find and fix a number of problems that's at least in the same general ballpark as this now-obsolete tool.
# JV16 PowerTools 2005: The current version of JV16 PowerTools is available in several flavors, all of which may be downloaded as uncrippled, fully functional trial versions; you pay if you decide to keep the software beyond the 30-day trial period. I used (and ultimately purchased) the full PowerTools suite ($30), which includes a number of system-maintenance tools along with the Registry Cleaner that's under discussion here. But the Registry Cleaner also is available in standalone form: RegSupreme ($13) and RegSupreme Pro ($17). The PowerTools Registry cleaner has two settings -- regular and aggressive, again to help prevent over-cleaning -- and also categorizes the problems it detects so you can help see and separate the serious problems from those that are less so. On our test system the PowerTools 2005 Registry Cleaner's "aggressive" setting dug far deeper than its simpler, earlier cousin (above), finding and removing a total of 800 problem items, including 53 "highest" level problems, 691 "moderate" problems, and 56 "low-level" problems. Unlike the earlier version, the Registry Cleaner, by default, only shows you Registry items that should be safe to remove; and like the earlier version, lets you examine each reported problem item one by one, if you wish, to help you be sure that any changes you make will be positive ones. However, the tool also offers to make a backup of all items you remove so you can easily restore any Registry settings you delete in error. In use, the tool felt polished and well-thought-out. Its only surprises were positive ones: for all its power, it was very easy to use. It also showed the most desirable outcome in repeated runs: a stable, repeatable, and very low number of errors (zero and one, respectively, the latter being a reference to a font that wasn't needed -- truly minor.) This combination of high initial-scan results, with low, stable repeated-scan results, is excellent performance.
Several years ago, when the old freeware versions of JV16 PowerTools went commercial, EasyCleaner became the de facto leading freeware Registry cleaner. It's still free today, although the author accepts (and deserves) donations. EasyCleaner went through some growing pains a few years ago, but has matured nicely into a small suite of system-maintenance tools that seems to work reliably and well. In my tests, EasyCleaner found and removed 99 entries on its first pass -- on rough par with the old version of JV16 PowerTools. The second and third runs found zero additional items, meaning that the tool found and removed everything it could the first time, just as it should have, with no artificial number-pumping going on to try to impress you. EasyCleaner is a very nice little tool, and you sure can't beat the price!
# Registry Mechanic: This two-part tool starts with a free download of a limited/crippled version of the software. I ran it; it found and removed 39 errors while informing me that the $30 paid/registered full version would remove an additional 58. The tool has a nice interface and runs quickly, but seems excessively conservative; detecting the second-lowest number of problems in our test. Repeated runs turned up 19 problems each time. I have no way of knowing if these were 19 new problems, or 19 of the initial 39 that weren't really fixed, or 19 that came back after reboot, or what. But the combination of a low initial error count results and relatively high repeated count puts this tool on my "don't bother" list.
# Registry Repair: This $30 software (15 day free trial) really sparked my interest in its first run when it reported it found and fixed an impressive 691 problems. But my interest faded quickly when the second run reported 124 items, and the third run reported 200 items. To me, that's a sign of something very wrong going on: either the program is introducing new errors as it runs; or is failing to correct some errors it reports; or is falsely reporting as "errors" things that are not really errors at all. Whatever the reason, I prefer not to trust my Registry to software that exhibits behavior like this. Why take a chance, when there are other tools available that don't behave this way?
# Registry First Aid: A $28 program with a limited/crippled trial version available, Registry First Aid found 59 problems on first run, less than what the old JV16 version could do. The software's interface is very nicely done, making it easy to see exactly what the program's doing; and to explore the various problems it has found and wants to correct. Alas, the second and third runs showed a real problem, reporting 123 and 109 problems, respectively; higher than the number found in the original run! I don't know what's going on here, and it's not worthwhile spending time to find out when there are other, better tools available.
# RegistryMedic: This $30 software is available in a free trial version that's hobbled to fix just five Registry errors per scan; with that, you can get a rough idea of how the software works, but that's all. The interface is clean, informative, and crafted in an XP-style, and so looks very much at home on the XP desktop. However, that may be the best part of the software: The initial scan on my test system turned up an even 100 problems, with the second and third scans turning up 80 and 68, respectively. The initial "100" didn't alarm me, as it's close to the number of "safe to fix" items reported by the old JV16 version, but if your initial scan starts at 100, how on earth can an immediate rescan still show 80 problems? That's a big red flag for me, and so I set aside this software, as well.
# The Registry Drill: This $40 tool bills itself as "the worlds most detailed Registry diagnostic tool available today. It will find hundreds of errors that other Registry Cleaners cannot." It takes safety to its logical conclusion: "It will not automatically delete any Key, it will post them for your review, telling you why the Key contains an error. You can repair the Key or delete it. The in-depth help file will walk you through all the repairs." This is good, in that the tool is unlikely to trash your system in any way. But when you're talking about hundreds of entries, a fully manual approach also has obvious drawbacks: It's going to take a long time to run, and you have to know what you're doing. Curiously, and in contradiction to the above, the software does offer a semi-automated "Auto Clean the Registry" option, which will perform a basic cleanup for you. In my tests, the Registry Drill found 134 items in its first pass, 110 in the second, and 109 in the third. These lackluster repeat performances, plus an antiquated-looking interface, and a setup that makes it clear that XP support was bolted on to a much older product, all help convince me that this is not a top-tier tool.
# RegistryFix: Like many of the other tools in this test, this software is available as a crippled/limited trial version (that will repair just a few problems) and a full version that purports to fix everything the software finds. In my tests, the software flagged 105 problems on the first run, 66 on the second, and 55 on the third. The program's interface is nice enough, but the results weren't anything special. I see no particular reason to select and use this software.
# CleanMyPC: The "registry-cleaner" module is free and will repair Registry problems two per run, until you pay $30, after which it will try to fix everything it finds. In my tests, the software found 130 problems on the first run, 114 on the second run, and 112 on the third; another lackluster performance that doesn't seem to warrant a deeper look.