Need a little more information - have you successfully loaded cities before? Are you trying to claim a new city, or enter one that you've played in the past? Are you playing multiplayer (online) or single player (offline)?
Some quick things to try regardless of the above: Set your desktop shortcut to "run as Administrator"; double-check that SimCity and Origin are both added to exception lists for your firewall and antivirus. Disable or uninstall BitDefender if you have it installed. Right-click SimCity icon in Origin, choose game properties and check the box that says "disable Origin in game for this game".
Some quick things to try regardless of the above: Set your desktop shortcut to "run as Administrator"; double-check that SimCity and Origin are both added to exception lists for your firewall and antivirus. Disable or uninstall BitDefender if you have it installed. Right-click SimCity icon in Origin, choose game properties and check the box that says "disable Origin in game for this game".