You may need to try uninstalling and reinstalling iTunes again. There is a specific order for uninstalling the components of iTunes that needs to be followed in order to ensure a successful uninstallation, and that order can be found in an article right here:
Use the Control Panel to uninstall iTunes and related software components in the following order and then restart your computer:
- Apple Software Update
- Apple Mobile Device Support
- Apple Application Support (iTunes 9 or later)
Important: Uninstalling these components in a different order, or only uninstalling some of these components may have unintended affects.
The full instructions for this process can be found in this article:
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