Recently, we attempted to answer the question, “Do I need a Registry Cleaner?

In the comments, we were challenged to review Registry Booster 2 [affiliate]. We already had an evaluation copy, so we decided to check it out.

The Windows registry is a central store for all system settings and options. It contains the information for all installed hardware, software, users, preferences, OS updates, etc. The registry is core to the operation of Windows. Invalid registry entries can cause system errors, crashes, and even refusal to boot.

Registry cleaners promise to clean up the entries left behind by uninstalled programs, remove errors in registry settings, and by doing so improve the performance and stability of a system. From the Registry Booster 2 website:

Have you noticed that the longer you have your computer, the slower it runs and the more it crashes? Often this phenomenon is caused by problems in the registry that accrue over time. Installing and uninstalling programs leave behind fragments – stray files, orphaned startup tasks, corrupted drivers. Over time the registry starts to get bogged down and conflicts emerge. Left unchecked, your system will become increasingly unstable, run more slowly and crash more frequently.

We decided to run tests using two different systems: a Windows Vista 32-bit desktop system with an Intel Core duo processor and 4GB of Ram; and a Windows XP Pro notebook with a Pentium mobile CPU and 1 GB of RAM.

First up is the Windows Vista desktop. This system is a test box that sees a lot of abuse. It’s seen MANY hardware changes, operating system changes, and had dozens of programs installed and uninstalled. If any system can benefit from a registry cleaner, it should be this one. We’ll be measuring boot time, shutdown time, and the time it takes to load Adobe Photoshop CS2 and Microsoft Word. Before making any modifications to the registry you should always backup. Registry Booster 2 has a registry backup feature. In addition to running this backup, we used ERUNT and created a System Restore point.

Registry Booster 2 has a nice looking, clean interface, and is simple to use:


After scanning, it reports 847 problems/errors found:


It took less than a minute to perform its cleaning:


Repair complete:


There’s also an option to defrag, which we did:


Registry Booster reported it found 847 errors, and repaired 835. Did it make any difference?

Windows Vista makes it easy to measure boot and shutdown times. Open the control panel, then Administrative tools, and finally the Event Viewer. In the Event Viewer tree select Applications and Services Logs, then Microsoft, Windows, Diagnostic-Performance, and Operational. Here we can find the boot and shutdown durations measured in milliseconds:


The system was booted five times. The high and the low times were tossed out, and the remaining three averaged. The results are shown below:


Boot time improved from an average of 73.517 seconds to 65.133 seconds, an improvement of 12.9%, or more than 8 seconds.

Even more impressive were the results noticed loading Photoshop. Load time improved from an average of 11.5 seconds, to 9 seconds. That’s a 27.8% improvement, or 3.5 seconds faster.


Microsoft Word showed some improvement, but since it loads on average in less than 5 seconds, it wasn’t significant. It was measured to start about .5 seconds faster.

Application loading times were measured with a plain old stop watch. The program was started five times. Again the high and lows were tossed out, and the remaining three times averaged. It should be noted the program start times were all measured after a system boot. With sufficient memory, Windows Vista will load programs significantly faster after they’ve been started once. There was no change in shutdown time.

Being skeptical of registry cleaners, we were surprised with the results. There was no denying the significant improvement in boot time, and loading time of some programs. Let’s see how the other system performs.

Next we tested the Windows XP notebook. This system hasn’t seen as much use. It hasn’t seen any changes to hardware and few changes to software. It doesn’t seem like such an obvious choice for a registry cleaner, and offers a good contrast to the first test system.

To measure boot times on Windows XP notebook we installed Microsoft bootvis. After each boot it provides a report including total boot time. We used the same method of booting five times, throwing out the high and low, and averaging the remaining three. Before Registry Booster the average boot time was 71.5 seconds. After Registry Booster it was 62.5 seconds.


Even though this system has seen far fewer changes over the life of the system, it still saw boot times improve by an impressive 14.4%, or 9 seconds. Unfortunately, we didn’t have Photoshop installed on this system. Microsoft Word was installed, and again saw just a minimal improvement of about .5 seconds. There was again no change in shutdown time.

Other Registry Booster 2 claims of reducing crashes, and improved system stability are more difficult, if not impossible to test. Neither of these systems were suffering from any crashes or stability problems. We debated introducing some errors into the registry to see if they were fixed, but decided it would be far from a real-world test, and opted against it. We did run each system for a couple of weeks after running Registry Booster. Neither system exhibited any new errors or crashes, which has been a problem reported with some other registry cleaners.

We began this test skeptical of registry cleaners in general. Computer support forums such as ours often have topics from people that have had bad experiences. However, if your expectations are realistic, we would have no problem recommending Uniblue’s Registry Booster 2. It’s easy to use, has a nice interface, and takes only a few minutes. It will provide improvements in boot times, and application loading times. It will not be able to cure every system crash, or stability issue. Maybe most importantly, it doesn’t create any new problems. If you’re in the market for a registry cleaner, Registry Booster 2 is a good choice. Click here to download, and run a free scan.

Please comment and share your experiences with Registry Booster, or other registry cleaners.