Why Registry Cleaners Are Useless

Registry cleaners are more trouble than they're worth.  This is mainly for one reason: The Registry is only accessed sequentially by registry cleaners.  All other applications access individual keys/values through the Windows API, which uses an indexed tree to quickly locate information.  The only apps you're speeding up by using a Registry cleaner are Registry cleaners.  Also, it should not be the job of any one application to determine what Registry information is or is not important.  Destroying empty keys is a bad idea because some application might purposefully create such things to store a hierarchy.  Destroying references to nonexistent files is a bad idea because some application might be storing that information as an indicator of the next file to create.  The companies that publish cleaners like this spread misinformation about systems needing to be cleaned up when it is in fact the cleaners that cause Registry-related instability in the first place.