Windows 126 error 7
Thank you for the details of the issue you are experiencing with installing the latest iTunes update. I recommend following the steps below:
1. Remove iTunes and related components from the Control Panel
Use the Control Panel to uninstall iTunes and related software components in the following order. 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.If you encounter an error while uninstalling, try repairing the affected component:
2. Verify iTunes and related components are completely uninstalledIn most cases, removing iTunes and its related components from the Control Panel will remove all supporting files belonging to those programs. To fully resolve these issues, manually remove any remaining iTunes-related folders listed below.On 32-bit and 64-bit systems:On 64-bit systems:
3. Reboot your computer.
4. Download the iTunes installer. When prompted to select what you want to do, choose to save it to your computer.
5. Install iTunes.
Right click on iTunesSetup or iTunes64Setup.
Windows Vista, Windows 7, and Windows 8: Select the 'Run as administrator' option.
Windows XP: Select the Open option.
Finish installing iTunes.
It is important to uninstall iTunes and the related components in the order listed in the first step.
You can find the full article here:
iTunes 11.1.4 for Windows: Unable to install or open
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