iTunes could not connect to the iPhone because an unknown error occurred (0xE8000065). One of these four solutions should resolve the error.
Upgrade iTunes
Using an out-of-date iTunes version can occasionally cause iPod, iPhone and iPad sync problems. Upgrade to the latest iTunes version, restart Windows, and then try to synchronize again. While you’re at it, verify that you have Windows fully patched by checking Windows Update for any pending software installations.
Check Your Firewall
Security software settings can be too restrictive and block programs that need system resources. To check if your firewall is the cause, temporarily disable it and try to sync your Apple device. Reconfigure your firewall settings if this was the problem. Some corporate networks block the specific ports that iTunes uses to connect to Apple. Check with your system administrator or company help desk if you must sync a company-sponsored Apple device with iTunes while on a business network.
Verify Driver Integrity
Check if the Apple Mobile Device USB driver is working in Device Manager.
Adjust Power-Management Options
You can also adjust the USB power management option. While still in Device Manager:
