Welcome to the Apple Support Communities!
In this situation, I would completely uninstall iTunes and all of its components from your computer (Bonjour included). Once uninstalled, download iTunes and install fresh. Please use the attached article as a reference.
Remove iTunes and related components from the Control Panel
Use the Control Panel to uninstall iTunes and related software components in the following order and then restart your computer:
2. Apple Software Update
3. Apple Mobile Device Support
5. 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.
Have a great day,