Firewall, Proxy, Router and Port Configuration


For assistance configuring security software, refer to the documentation provided with the software or consult the manufacturer's website.

In some situations, disabling security software temporarily may provide a workaround for connectivity issues. For assistance, visit our Disabling Security Programs guide.

Most proxy servers, firewalls, and other Internet connection sharing methods can restrict port access. Your configuration may be restricting packets from unknown sources. In order to connect to and allow others to connect to games you create, make sure you have the following ports through Local Area Network (LAN) set up as described below:
TCP PORTS UDP PORTS Desktop Application 80, 443, 1119 and 6881-6999 80, 443, 1119, 6881-6999
Blizzard Downloader 1119, 1120, 3724, 4000, 6112, 6113, 6114, 6881-6999 1119, 1120, 3724, 4000, 6112, 6113, 6114, and 6881-6999
Diablo 6112-6119 6112-6119
Diablo II 6112 and 4000 None
Diablo III 80, 1119, and 6881-6999 1119, 6881-6999
Hearthstone 1119, 3724 1119, 3724
StarCraft 6112 6112
StarCraft II 1119, 6113, 1120, 80, and 3724 1119, 6113, 1120, 80, and 3724
Warcraft II Edition 6112-6119 6112-6119
Warcraft III 6112 (Default) and 6113-6119 None
World of Warcraft Launcher and Game Client 3724, 1119, 1120, 4000, 6112, 6113, 6114, 80, and 6881-6999 3724, 1119, 1120, 4000, 6112, 6113, 6114, 80, and 6881-6999

To configure a firewall for your specific operating system, select it below:

Windows XP Service Pack 3

Service Pack 3 is required to be installed to run Blizzard games on Windows XP. Follow the steps below to start the installation process:

  1. Click Start > Control Panel > Security Center > Windows Firewall.
  2. Under the General tab, be sure you have On (recommended) selected:
  3. Click the Exceptions tab.
  4. Click the Add Port... button.
  5. In the Add a Port dialog add port 3724 as follows:
    Name: Blizzard Downloader
    Number: 3724
    Select TCP
    Click OK. This will return you to the Exceptions tab
  6. Click Add Port... to add another port.

Repeat the steps above for each port you need opened. These ports should be added to the firewall:

  • 6112 TCP
  • 1119 TCP
  • 1120 TCP
  • 4000 TCP
  • 6113 TCP
  • 6114 TCP
  • 4000 TCP
  • 6881-6999 TCP (The Windows Firewall doesn't have a feature for adding port ranges, so each of these ports will need to be added individually).

Your firewall should now allow traffic on the necessary ports for proper Blizzard Downloader operation.

Windows 7

  1. Click Start > Control Panel > System and Security > Windows Firewall.
  2. On the left frame, click Advanced Settings > Select Inbound Rules.
  3. On the right frame, click New Rule...
  4. Select the Port radio button and click Next.
  5. Select the TCP radio button.
  6. In the Specific Local Port field, enter 3724. Click Next.
  7. Select the Allow the connection radio button. Click Next.
  8. Make sure Domain, Public, and Private boxes are all checked. Click Next.
  9. Enter any name for this rule. Click Finish.
  10. Repeat the steps 3-9 for TCP port numbers 1119, 1120, 4000, 6112, 6113, 6114, and 6881 - 6999. If you wish to use Voice Chat, also repeat steps 7-13 for UDP port numbers 1119 and 3724.

You can now close all the windows you opened. Your firewall should now allow traffic on the necessary ports for proper Blizzard Downloader operation.

Mac OS X

The firewall in Mac OS X is an Application Firewall, which allows you to control connections on a per-application basis, rather than a per-port basis. This makes it easier to gain the benefits of firewall protection and helps to prevent undesirable applications from taking control of network ports that have been opened for legitimate applications.

  1. From the Apple menu, choose System Preferences > Security.
  2. Click the Firewall tab.
  3. Unlock the pane by clicking the lock in the lower-left corner and entering the administrator username and password.
  4. Click Start to enable the firewall.
  5. Click Advanced to customize the firewall configuration.
  6. Check the Automatically allow signed software to receive incoming connections box.
  7. Click OK.

Blizzard does not directly support proxies, firewalls, or routers. You may need to contact your ISP or network administrator for assistance if you have opened the correct ports but still cannot connect. For assistance with configuring your router or firewall, contact the manufacturer. is a useful third-party site that contains port forwarding walkthroughs for most router models.

Get Help

Still can't find a solution? Submit a ticket and someone will help out!