Registry cleaners always make us a little nervous; too often they contain entirely too little information about what they're doing and the potential risks involved in tinkering with the registry. Occasionally we encounter registry cleaners that do a particularly good job of helping users make wise decisions about their use, but unfortunately Genuine Registry Doctor is not such a program.
Genuine Registry Doctor opened and immediately began scanning before we had a chance to even realize what was going on. When the scan was done it listed the number of problems found in each of four categories--Registry Clean, Privacy Sweep, Junk Files Removal, and System Optimization--and then asked us if we wanted to "cure these right now." Since we had no idea what the program had actually done or what it wanted to cure, and especially since it hadn't given us a chance to create a backup of our registry, we declined.
We were then able to take a look at exactly what Genuine Registry Doctor had found. Broken shortcuts, missing uninstaller files, unsupported file types, and plenty of other issues that made varying levels of sense. The program has a brief online FAQ that doesn't go into any detail about what kinds of errors it finds and fixes. We finally decided to at least try fixing some of the Privacy Sweep issues, figuring that our browsing history in seldom-used Internet Explorer would be a safe thing to get rid of. But when we clicked the Cure button, we got a message informing us that this version of Genuine Registry Doctor can only fix five errors at a time, and users must purchase an upgrade to be able to do more.
That was all we really needed to see of Genuine Registry Doctor; there are plenty of other programs out there that do a thorough and safe job for free, and we recommend seeking those out instead.