Every time new software or updates, especially from Microsoft, that occurs, and they are mainly registry entries that need changing that Microsoft's setup program simply does not handle very well.
Bottom line . . . believe it and let WinDoctor fix it. (It normally deletes those entries which refer to removed or changed file names.)
This is one of the reasons for Windows' chronic instability.
As an example . . . a reinstall of Windows over itself can produce as many as 60 or 70 of these erroneous Active X entries. Windows is very slip shod when it comes to cleaning up its own registry.