iTunes not installed properly

There are a number of reasons that might cause iTunes to not be installed properly. You can troubleshoot the problem by using the list below as a reference. Try to check one item at a time and reinstall iTunes, since the cause might be just one or a combination of the items in the list.

1. There are temp files left over by a previous iTunes installation. Cleanup your computer's Temp directory.
2. A previous iTunes version and related components have not been removed prior to installation. Make sure the following programs have been completely removed from your computer:
1. iTunes
2. QuickTime
3. Apple Software Update
4. Apple Mobile Device Support
5. Bonjour
6. Apple Application Support
3. Your iTunes installer might not be the latest version. Make sure to download the latest iTunes version from http://www.apple.com/itunes/.
4. You are not logged in as an administrator in your computer while installing iTunes.
   
5. The folder where the installer is saved might contain special characters. Make sure to keep the folder name simple in order to avoid any problems in the installation.
6. Your computer does not have the latest Windows updates. Make sure to apply the latest Windows updates.
7. Temporarily disable third-party software that would conflict with the iTunes installation, like your anti-virus software.