If you’re having any WiFi connection issues (such as frequent dropouts, slow speeds or you simply can’t connect) with Mac OS X Lion, there are a few things that you can do to troubleshoot and hopefully restore connectivity to your Mac. WiFi can be the most convenient way to connect to the Internet, but it’s not occasionally without its difficulties – possibly problems with your Internet Service Provider, the local access point (i.e. your router or hub), or other technical issues (hardware or software) with the Mac.
Follow our brief guide below to troubleshoot some of the most common WiFi issues you might encounter with Lion.
Check Your Mac’s WiFi Settings
The first thing to do when you’re experiencing WiFi problems is to check and validate your network settings in System Preferences to make sure everything is setup correctly.
1. Open System Preferences and select the Network icon, which is in the Internet & Wireless section
2. Click the Advanced button at the lower right to view more details about your network connection
3. Under the TCP/IP tab, under most circumstances you’ll need the Configure IPv4 item set to Using DHCP. The reason is that in OS X Lion there have been some reports that manual configuration causes issues (though this may only be with early versions after the OS was first released)
4. You should also look at the other network tabs such as Wi-Fi, and check that the network you want to join is shown in the list. Drag the networks into the desired order, for example you may as well move the network that you want to connect to right to the top of the list to make sure your Mac looks for that one first
It’s also definitely worth just plugging in a network cable between your router and your Mac, to check whether basic Internet connectivity is working. If you can’t even connect to the Internet with a cable, then it points to a broader problem that may not be related to WiFi.
Remove and Re-Add The WiFi Service
One thing to try when you’re experiencing wireless network problems is to delete and then re-add the WiFi service.
Follow the steps below:
1. Open Network settings under System Preferences
2. In the left-hand side panel, select the Wi-Fi icon and then hit the Delete button (the small “-” icon) and confirm when prompted
3. Once the WiFi service has been deleted, add a new one with the Add (“+“) button, and then enter the name of the new connection followed by Create. This establishes a new WiFi connection with the default settings. Just go through the various tabs to make sure WiFi is configured correctly (items such as the password) and try connecting to your wireless hotspot again. If prompted, re-enter any details that may have been lost when deleting the service
Check Your Wireless Router Settings
Your wireless router is normally provided by your Internet Service Provider (ISP) when you sign up to an Internet, phone or TV package. Sometimes however it’s necessary to reset the router (there should be a small reset button on the back), or even login to it and play around with the settings to use the optimal configuration. Unfortunately, quite often the administrator password isn’t provided to customers to stop them changing the default settings accidentally. If you know the password, it’s definitely worth logging in to the router to inspect the configuration.
To get to your router, open a new tab in Safari and enter the following address in the address bar:
This should take you to the router’s login / administration page where you need to enter its admin user name and login password. If this address doesn’t work, you can try one of the other default addresses commonly used by routers, such as 192.168.2.1 and 192.168.1.1
Make sure that you take a look at the security settings (such as the wireless key) and inspect the logs to see if there are any clues about potential issues. Every router is different, so there’s not one set of specific instructions that works across all models, but in general a few tweaks can usually help resolve your WiFi connection issues. For example, if there are dozens of WiFi hotspots in the area where you live, you might be subject to wireless interference issues if someone else has configured their router to use the same wireless channel – try changing it from the default channel to something different. You can also change the security settings (for example to use WPA or WPA2) or remove them completely, to see if that makes a difference.
Try Connecting Other Devices
It might seem pretty obvious, but you should always try connecting another device over WiFi to see if it’s actually your Mac or the wireless network itself which is experiencing technical issues. If you can successfully connect another computer, iPhone or tablet for example, then it points to an issue with your Mac rather than the network kit or Internet connection.
Also, you should of course try connecting your Mac to another wireless network to see whether the problem persists. If you can connect to another WiFi setup, then consider noting down the router’s configuration and setup details and comparing that to your own.
Reset PRAM and SMC
Your Mac’s Parameter RAM (PRAM) memory can occasionally be the cause of various technical issues, so if you have WiFi woes and nothing seems to work you could try to reset it. Follow the procedure below:
1. Shut down your computer
2. Locate the Command, Option, P and R keys. You’ll need to use these in a moment in step 4
3. Turn on the computer
4. Press and hold down the Command, Option, P and R keys before the grey screen appears
5. Hold down the keys until the computer restarts and you hear the startup sound for the second time
6. Release the keys
The PRAM should now be reset to the default values. Try connecting to the Internet by WiFi again when your computer has fully rebooted.
Another approach is to reset the main SMC chip (System Management Controller), which may resolve issues related to fans, lights, video and power. If you’ve tried everything else and you still can’t get your WiFi to work, you may as well reset the SMC, as there aren’t any negative consequences of doing so.
1. Shut down the computer
2. Plug in the power adaptor
3. Press the Shift + Control + Option keys and the power button at the same time
4. Release all the keys and the power button simultaneously
5. Press the power button to turn on your Mac
Delete The Internet Preference Files
You can try deleting some of the Internet preference (.plist) files from your system Library folder. Sometimes, corrupted preference files can be responsible for things not working correctly. Follow these steps:
1. In Finder, press Command + Shift + G and in the drop-down dialogue box, enter ~/Library as shown below:
2. Locate the following preference files
3. Copy the files somewhere (e.g. to your desktop) as a precaution and then delete them from the Library folder. Any similar files named com.apple.internetconfig[...] can also be safely deleted
4. Turn your Mac’s airport off and back on (just click the airport symbol in the menu bar and choose Turn Wi-fi Off)
Call a Professional!
Finally, if you’ve exhausted every possible avenue and still can’t resolve your WiFi connection issues, it might be time to concede defeat and take your Mac to the Apple Store to see if they can resolve the issue. Most problems with your Mac should be fixable by the technicians there, but there are of course lots of resources on the Internet that you can also use.