If you have incorrect proxy settings in iTunes on PC
If you have incorrect proxy settings, iTunes for Windows gives you an error message when it tries to connect to internet content, such as the iTunes Store, CD information (CDDB), or Apple Music.
If you get such an error message in iTunes, see whether other internet applications, such as your web browser and email client, are able to connect. If they can’t, you need to do some general internet troubleshooting. If your web browser can connect to the internet but iTunes can’t, you may need to configure your web proxy settings.
iTunes uses the web proxy settings from Internet Explorer when accessing internet content. If your network uses an HTTP proxy, make sure that the settings are correct, or try disabling them.
On your PC, go to Start, then click Control Panel.
In the Control Panel in Windows Vista, click Network and Internet, then click Internet Options.
Alternatively, in Control Panel in Windows XP and Classic View of Control Panel in Windows Vista, open Internet Options.
In the resulting dialog, click Connections, then click the LAN Settings button.
In the Proxy Server section of the Local Area Network Settings window, verify that your proxy settings are correct. If they’re not, correct them, then skip to step 5.
If your settings are correct, try turning the proxy off for troubleshooting purposes. To do this, deselect the “Use a proxy server for your LAN” checkbox.
Click OK in both the LAN Settings window and the Internet Options window.
In iTunes, try to access the iTunes Store or Apple Music.
Whether or not this resolves your issue, double-check your proxy settings with your local network administrator.