Frederick,
Thanks for your response. Well then, are there any reliable PC cleaners/optimizers out there? I'd still like to know what those TyoeLibReference messages refer to.
eaglecap
There aren't any reliable registry cleaners/optimiziers for the simple reason that the registry does not need cleaning or optimizing. Over time it can easily acquire some minor flaws, e.g. because some uninstallation program fails to remove all registry keys it owns. This makes no difference to your PC's performance, same as having a few freckles makes no difference to your running speed. You could, of course, remove them surgically but why would you take the risk?
When you have a registry problem then Windows will inform you in no uncertain terms.