Computer Already Authorized

I have a new laptop with Windows 10. I have iTunes downloaded and the laptop authorized. When I try to sync my iPhone 5c, I get an error message that the purchases can't be synced because the computer hasn't been authorized. I have used the following link:

https://support.apple.com/en-us/HT203160 and have performed all the steps. I have uninstalled & reinstalled iTunes, logged out of my iTunes profile multiple times and have logged off my computer multiple times. Any other ideas as to how I can get my iPhone to sync?