I never realized before that the most common registry errors are caused by programs not being completely removed.  I learned this when I started looking for ways to make my system run a little faster, like it did when I first got it.  I have a habit of installing all kinds of programs and then uninstalling them when I no longer use them. I had no idea this was causing so many problems.  It didn’t happen right away; it took awhile before enough fragmented files accumulated to cause problems.  Now I am reviewing all the registry repair programs in order to find one that will work well for my operating system.