Mac Won’t Connect to Wi-Fi? Work Through These Six Steps
“My Mac suddenly cannot connect to Wi-Fi but other devices are fine”
First work out whether it is one network or all networks. If other devices are fine, the problem is on your Mac, and forgetting then re-adding the network fixes most cases.
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Toggle Wi-Fi off and on. If that does not help, restart both the router and the Mac. Those two steps resolve roughly half of all cases.
What you are seeing
- Wi-Fi icon is greyed out or shows an exclamation mark
- The network appears but disconnects immediately after joining
- It connects but there is no internet access
- No Wi-Fi networks show up at all
Common causes
- A corrupted saved network configuration
- IP address conflict or a DHCP assignment problem
- A broken network location profile
- Router band or encryption incompatible with macOS
- Leftover VPN or proxy configuration
Full walkthrough
- 01
Establish the scope of the problem
Try the same network on your phone. If the phone works, the router is fine and the issue is on the Mac. If the phone also fails, restart the router first. This prevents you from troubleshooting in the wrong direction.
- 02
Forget the network and rejoin
In System Settings → Wi-Fi → Details, choose Forget This Network, then reconnect and re-enter the password. This clears the stale configuration and is the single most effective step.
- 03
Check VPN and proxy settings
A surprising number of network problems trace back to a VPN that did not exit cleanly, or leftover proxy settings. Check System Settings → Network → VPN, and Details → Proxies, then disable them.
- 04
Reset the network location
At the bottom of System Settings → Network you can manage locations and virtual interfaces. Creating a new location bypasses a corrupted profile.
sudo ifconfig en0 down && sudo ifconfig en0 up⚠️ Heads upen0 is usually Wi-Fi, but it can differ by model. Confirm with networksetup -listallhardwareports before running this. - 05
Delete the Wi-Fi configuration files
If nothing else worked, remove the stored Wi-Fi preferences and let macOS rebuild them on restart. This clears all saved Wi-Fi passwords.
sudo rm -rf /Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist⚠️ Heads upYou will need to re-enter every Wi-Fi password afterwards. Make sure you know them before running this. - 06
Rule out the router side
Check whether the router uses MAC address filtering, a specific band only, or an encryption mode macOS handles poorly — some WPA3 mixed modes are known culprits. Temporarily switching to WPA2 is a useful test.
How to prevent it
- Restart your router periodically rather than leaving it running for months
- Avoid saving duplicate or conflicting network profiles
- Quit your VPN when you are done instead of leaving it connected
Follow-up questions
Why is it only my Mac?
Most often a corrupted saved configuration on the Mac, or a DHCP assignment issue for that specific device. Forgetting the network and rejoining usually resolves it.
What happens if I delete that plist?
All saved Wi-Fi networks and passwords are cleared and must be re-entered. Nothing else in the system is affected.