Activate your firewall: Mac OS 10.6 (Snow Leopard)
A firewall protects your computer from Internet worms that exploit open ports and operating system vulnerabilities. Follow these instructions to activate the firewall on your Mac OS 10.6 (Snow Leopard) computer.
You should activate only ONE firewall on your computer.
- From the Apple menu, click System Preferences.
- In the System Preferences window,
click the Security icon in the
top row, highlighted in the following
- In the Security window, click the Firewall tab.
- If not already enabled, click Start
to turn on the firewall. The window
should now look similar to the
- Click Advanced in the lower-right corner of the window.
- Check the Block all incoming
connections check box if it's not
already checked. This should also
automatically check Enable stealth mode
near the bottom of the window. The
window should now look similar to the
- Click OK.
- Close the Security window.