For your host or your guest? What is your host? I was hoping that you meant to describe the usefullness of that product when I read the topic. However, it seems to be a question - not a description of how you have successfully used something to make Parallels a better product. Perhaps you should read how Parallels chooses to define their forum contents and choose a place where your question would have a better chance of being answered. I've never used a registry cleaner, because most of them are 3rd party products from obscure web sites, and I would be concerned that they would cause more problems than they would solve. Parallels makes it easy to backup a windoze installation so that if anything bad goes on, you just have to copy a file to recover. It's the 2nd best solution to using a basically insecure OS. The best solution is just to use Linux and let the windoze monoply die out like IBM did long ago.
tgrogan is right on several counts: 1) This isn't the right place for questions 2) The windows registry is one of the dumbest pieces of programming in the history of operating systems, and a nightmare to troubleshoot. There is no need for this kind of kludge in any flavor of UNIX, including the MacOS. But given that some of us are stuck with windows for the time being, I've had experience with Registry Cleaner, which isn't one of those obscure pieces of software that easily hoses your system. I have never had a problem with it rendering my system inoperable, as long as I played it safe, and did the mildest level of cleaning. On the other hand, if you have a fairly new and clean installation of XP which is working OK, I would stay away from it. If your system is behaving very badly under Parallels, then you might want to consider it. But I would back up your entire VM to a safe location before doing so, in case it does some damage.
