Jouni Vuorio, programmer of the popular jv16 Powertools has run a little test of 26 renowned registry cleaning tools including his own. While some might say he did it to promote his software, I am rather astonished by his findings. Most shareware and professional tools are not as thoroughly as his freeware and might even damage the registry. To remove all doubts Jouni has made all testing material available for download so you can verify his findings.

Nearly all of the most commonly used cleaners report many valid registry entries as invalid. This means only one thing, those programs are very badly designed and coded. And what disturbs me even more is that many of these software are commercial, I can't really understand how any software company can sell this kind of software with full price! Read the test