For the best user experience with Back to My Mac, use OS X Mountain Lion or OS X Lion v10.7.5 or later (use Software Update to download and install the latest updates). Also, make sure your router supports NAT-PMP (NAT Port Mapping Protocol) or UPnP (Universal Plug and Play), and that it's enabled.
The Back to My Mac feature of OS X is designed to work seamlessly with compatible AirPort base stations. Please make sure that your AirPort software is up to date. This seamless integration is achieved through the use of NAT-PMP (NAT Port mapping Protocol) technology, which enables your computer to automatically configure your AirPort base station to provide services between your local network and the Internet.
Some third-party Internet routers use a technology called UPnP (Universal Plug and Play), which is similar to NAT-PMP. Back to My Mac works with both NAT-PMP and UPnP.
If Back to My Mac isn't working
Follow these instructions to turn Back to My Mac on in AirPort Utility 6.x
- Open AirPort Utility (in /Applications/Utilities).
- Find the appropriate base station and click its icon.
- Choose "Edit" in the pop-up menu.
- Click the + button in the Back to My Mac section.
- Enter your iCloud username and password, then sign in.
- Click Update to save changes.
- The base station's icon will become dimmed and its status will say "Updating..." until the base station is finished being configured. Quit AirPort Utility after the process is finished.
If Back to My Mac isn't working and you use a third-party router, make sure UPnP is enabled. Consult the device's documentation or contact the manufacturer for information about enabling UPnP.
For more information about setting up Back to My Mac, see Using and troubleshooting Back to My Mac.