Enable iTunes in the Windows Firewall on PC
When the Windows 8 or Windows 7 firewall is enabled, it may prevent iTunes from accessing the Internet unless iTunes is listed as an exception.
On your PC, click Start, then click Control Panel.
Click System and Security, then click Windows Firewall.
Click “Advanced settings.”
Click Inbound Rules (below “View and create firewall rules”).
Click New Rule (on the right side of the window).
In the window that appears, choose Program, then click Next.
Choose “This program path,” then click Browse.
Navigate to Program Files > iTunes, then click Open.
Select iTunes, click Open, then click Next.
Select when the rule applies, then click Next.
Type a name for the rule, then click Finish.
If you are still having difficulty, visit the iTunes for Mac or Windows Support website.