I have a couple of links that should be able to help you with this issue. If your iTunes still says that it is on iTunes 11.0.5, then it still needs to be updated. Since you have been trying to update it previously, you may want to uninstall iTunes from your computer then try redownloading and installing the latest version. I have an article that can walk you through uninstallation, since certain components need to be uninstalled in a specific order:
After uninstalling iTunes from your computer, you can download the latest version again from the following link:
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