When your Mac suddenly loses its Wi-Fi connection, the cause could be on the Mac itself, on the router, or on the ISP side — or a combination of all three. Blindly resetting settings can waste a lot of time, so diagnosing the symptom first and then acting is the fastest path to a fix. This article covers macOS Sonoma and Sequoia on both Apple Silicon (M1/M2/M3/M4) and Intel Macs, walking you through concrete steps for each scenario: SSID not showing up, password being rejected, connected but no internet, slow speeds, disconnecting after sleep, and trouble with work/school Wi-Fi. If you're also having trouble on your iPhone, see How to Fix an iPhone That Won't Connect to Wi-Fi | Troubleshooting by Symptom.
Table of Contents
- Step 1: Identify Your Symptom
- Basic Fixes on the Mac Side
- Re-register the Network with "Forget This Network"
- Reset Network Settings (Moving the plist Files)
- Check the Router and Your Internet Connection
- Change Your DNS Servers
- Wireless Diagnostics Tool
- VPN / Proxy / Security Software
- macOS Updates and Known Bugs
- Work / School Wi-Fi (WPA2 Enterprise / 802.1X)
- When Hardware Failure Is Suspected
- Summary: Troubleshooting Checklist in Order
Step 1: Identify Your Symptom
The phrase "Wi-Fi isn't working" can mean very different things, and the right fix depends entirely on what exactly is happening. Check which description matches your situation.
SSID not appearing in the list
When you click the Wi-Fi icon in the menu bar, the network you want to join doesn't show up at all. Common causes include Wi-Fi being turned off, a router problem, being out of range, or the Mac not supporting a 5 GHz-only SSID. Start by toggling Wi-Fi on the Mac off and back on, then try restarting the router.
SSID appears but connection fails (password rejected)
The network name shows up in the list, but entering the password either fails immediately or displays "Unable to join the network." Typical causes are a typo in the password, corrupted saved settings on the Mac, or MAC address filtering on the router. The "Forget This Network" approach described later is usually the fix.
"No Internet Connection" message
The Wi-Fi fan icon appears in the menu bar — indicating an active connection — but browsers can't load pages and show "No Internet Connection." This means the Wi-Fi link itself is fine, but traffic isn't reaching the internet beyond the router. The likely culprit is a DNS or IP address issue, or a problem on the router or ISP side.
Connected but extremely slow
You have a connection, but videos buffer constantly and web pages take forever to load. Channel congestion, connecting to the wrong frequency band (2.4 GHz instead of 5 GHz), DNS latency, an active VPN, or router overload are common causes. Switching frequency bands or changing DNS servers often helps.
Disconnects after sleep or after a macOS update
Everything is fine normally, but after waking from sleep Wi-Fi is gone and needs to be reconnected manually — or Wi-Fi became unstable right after a macOS update. Bugs in macOS sleep/wake management or inconsistencies in network configuration files are the usual reasons. Moving the plist files and resetting is effective here.
Only one specific Wi-Fi network won't connect
Home Wi-Fi works perfectly, but one particular café, workplace, or school network refuses to connect. Conflicts with the Private Wi-Fi Address feature, WPA2 Enterprise / 802.1X authentication problems, or a Captive Portal login page not appearing are typical causes.
Quick-reference table by symptom
| Symptom | Likely cause | First thing to try |
|---|---|---|
| SSID not in list | Wi-Fi off / router issue / out of range | Toggle Wi-Fi off/on / restart router |
| Password rejected | Corrupted settings / typo / MAC filter | Forget This Network and re-register |
| No internet connection | DNS issue / problem beyond the router | Change DNS / restart router |
| Connected but slow | Channel congestion / wrong band / DNS latency | Switch to 5 GHz/2.4 GHz / change DNS |
| Drops after sleep/update | macOS bug / plist inconsistency | Move plist files / restart |
| Only one network fails | Private MAC / auth settings / portal | Disable Private Address / check certificate |
Basic Fixes on the Mac Side
Regardless of the symptom, these are the first things to try. They fix a surprising number of cases on their own.
Toggle Wi-Fi off and on from the menu bar
Most temporary communication errors are cleared by this alone.
- Click the Wi-Fi icon in the upper-right menu bar.
- Click the "Wi-Fi" toggle to turn it off.
- Wait about 10 seconds, then turn it on again.
For a more thorough reset, use the toggle in System Settings → Network → Wi-Fi. The menu bar shortcut only disconnects from the current network — it may not fully reset the internal Wi-Fi state.
Restart macOS
A restart resets macOS's entire networking stack and clears temporary bugs. Go to Apple menu → Restart. Disconnections after waking from sleep are especially likely to be solved by a full restart.
Toggle Airplane Mode (macOS Sonoma and later)
macOS Sonoma (14.0) and later added an Airplane Mode toggle to Control Center. If it's accidentally turned on, all wireless connections — including Wi-Fi — are disabled.
- Click the Control Center icon in the upper-right menu bar.
- Check whether "Airplane Mode" is active (highlighted blue).
- If it is, click it to turn it off.
On macOS Ventura (13) and earlier, there is no Airplane Mode button in Control Center by default. You can check Airplane Mode status under System Settings → Network.
Wi-Fi network priority settings
When you've used multiple Wi-Fi networks, the Mac tries to auto-connect to them in priority order. It's possible the Mac is repeatedly attempting to join an old, unavailable SSID and failing.
- Open System Settings → Network → Wi-Fi.
- Click the "Details…" button on the right.
- A list of preferred networks appears.
- Select any unwanted networks and click the "−" button to remove them, or drag higher-priority networks to the top.
Re-register the Network with "Forget This Network"
If a network that used to work fine suddenly refuses to connect, the saved configuration on the Mac side may be corrupted. Deleting and re-registering the network often resolves this.
Steps to forget and reconnect
- Open System Settings → Network → Wi-Fi.
- Click the "Details…" button on the right.
- Select the problematic network from the list of preferred networks.
- Click the "−" button to remove it, then click "OK" to confirm.
- From the Wi-Fi icon in the menu bar or the Wi-Fi settings screen, select the SSID again, enter the password, and reconnect.
After forgetting and reconnecting, the Wi-Fi entry is registered from scratch, which resolves many "only one network won't connect" and "password keeps being rejected" problems. If you've forgotten the password, check the label on the back of your router — the default password is usually printed there.
Reset Network Settings (Moving the plist Files)
If configuration files have become corrupted at a deeper level, moving (backing up) the Wi-Fi-related plist files and letting macOS regenerate them can help. All saved Wi-Fi passwords will be erased, so note down the passwords for any networks you'll need to reconnect to before proceeding.
Files to move
The following three files under ~/Library/Preferences/SystemConfiguration/ are the targets.
- com.apple.airport.preferences.plist — saved Wi-Fi networks and priority order
- NetworkInterfaces.plist — network interface configuration
- preferences.plist — overall network settings (wired and Wi-Fi)
Steps
- Open Terminal (Spotlight → type "Terminal" and press Return).
- Create a backup folder on your Desktop:
mkdir -p ~/Desktop/network_backup - Copy the three files to the Desktop:
sudo cp ~/Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist ~/Desktop/network_backup/ sudo cp ~/Library/Preferences/SystemConfiguration/NetworkInterfaces.plist ~/Desktop/network_backup/ sudo cp ~/Library/Preferences/SystemConfiguration/preferences.plist ~/Desktop/network_backup/ - Delete the original files:
sudo rm ~/Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist sudo rm ~/Library/Preferences/SystemConfiguration/NetworkInterfaces.plist sudo rm ~/Library/Preferences/SystemConfiguration/preferences.plist - Restart your Mac — macOS will automatically regenerate the files.
- After restarting, reconfigure your Wi-Fi connections.
If the problem persists, you can restore the backed-up files to their original location (copy them back with sudo cp and restart).
Check the Router and Your Internet Connection
If nothing on the Mac side helps, the problem may be with the router or your internet service. The fundamental diagnostic is to check whether the same issue occurs on another device.
Test with another device
If an iPhone or another PC can connect to the same Wi-Fi without any problem, the issue is on the Mac side. If no devices can connect, the problem is with the router or your internet service.
- Check whether your iPhone can connect to the Wi-Fi (see How to Fix an iPhone That Won't Connect to Wi-Fi | Troubleshooting by Symptom for details).
- If you have another Mac or a Windows PC, try connecting it to the same SSID.
Restart the router
Routers are susceptible to memory leaks and other issues over long uptimes, and a restart clears most of them. Simply unplug the power cable, wait 30 seconds, and plug it back in.
If your setup has a separate home gateway and router, power both off, wait 30 seconds, then power the home gateway on first, followed by the router.
5 GHz vs. 2.4 GHz
Most modern routers broadcast on two frequency bands.
| Band | Characteristics | Best for |
|---|---|---|
| 5 GHz (Wi-Fi 5 / Wi-Fi 6 / 6E) | Fast, less interference, shorter range | Close to router, streaming, large transfers |
| 2.4 GHz (Wi-Fi 4 / Wi-Fi 5) | Slower, more interference, longer range | Distant rooms, through walls, IoT devices |
If your Mac keeps failing to connect to the 5 GHz band, manually switching to the 2.4 GHz SSID may work. Many routers distinguish the two with suffixes like "XXXXXX-a" for 5 GHz and "XXXXXX-g" for 2.4 GHz.
Also note: if you have a Wi-Fi 6E (6 GHz) router, Macs running macOS 12.1 or earlier cannot use the 6 GHz band. The latest MacBook Pro and Mac mini models support Wi-Fi 6E, but older Macs max out at 5 GHz.
Channel congestion
In apartment buildings, neighboring access points using the same channel cause interference that leads to slow speeds and instability. Setting your router's channel to "Auto" — or manually selecting a less-congested channel — can improve the situation.
You can visualize channel congestion with macOS's built-in Wireless Diagnostics tool (described below).
Change Your DNS Servers
If the Wi-Fi icon appears but pages won't load, or certain services are unreachable, the DNS server provided by your router or ISP may be having problems. Switching to a public DNS can resolve this.
How to switch to Cloudflare 1.1.1.1 / Google 8.8.8.8
- Open System Settings → Network → Wi-Fi.
- Click the "Details…" button on the right.
- Select the "DNS" tab at the top.
- Click the "+" button under "DNS Servers" and add the following:
- Cloudflare DNS: 1.1.1.1 and 1.0.0.1
- Google Public DNS: 8.8.8.8 and 8.8.4.4
- Leave any existing DNS entries (shown grayed out) as they are.
- Click "OK" then "Apply" to save.
To revert, select the DNS entries you added, click "−" to remove them, and click "Apply" — your router's DNS will be used again.
Wireless Diagnostics Tool
macOS ships with a built-in "Wireless Diagnostics" tool that goes far beyond a simple connectivity test — it can generate a detailed report on signal strength, channel interference, and connection quality.
How to launch it and generate a report
There are two ways to open it.
- Hold the Option key and click the Wi-Fi icon in the menu bar → select "Open Wireless Diagnostics."
- Use Spotlight (Cmd + Space), type "Wireless Diagnostics," and press Return.
Click "Continue" to start the diagnosis. If any problems are detected, hints for fixing them will be displayed.
For more detail, open the "Window" menu → "Info" inside Wireless Diagnostics to see real-time connection stats (RSSI, noise, channel, MCS index, and more). "Window" → "Scan" lists all nearby SSIDs and their channel usage, which is useful for spotting channel congestion.
VPN / Proxy / Security Software
A VPN, proxy, or third-party firewall/security app can block internet access even though Wi-Fi itself is connected.
Check proxy settings
If a proxy is misconfigured and left enabled, your browser may look like it has no internet while Wi-Fi itself is working fine.
- Open System Settings → Network → Wi-Fi.
- Click the "Details…" button on the right.
- Select the "Proxies" tab.
- If "Auto Proxy Configuration," "Web Proxy (HTTP)," or "Secure Web Proxy (HTTPS)" are enabled and you didn't set them intentionally, turn them off.
- Click "OK" then "Apply" to save.
Third-party VPN clients
VPN apps like NordVPN, ExpressVPN, or Mullvad may have a kill switch feature that blocks all internet traffic when the VPN connection drops.
- Quit the VPN app entirely and check whether you can connect.
- Temporarily disable the kill switch (sometimes labeled "Internet Kill Switch" or "Network Protection").
- Clear the VPN app's cache and restart it.
If a VPN interface is lingering under System Settings → Network and interfering, click "−" to remove it and then re-add it.
Third-party firewalls
Outbound firewall apps like Little Snitch, Lulu, or Radio Silence may be blocking certain processes from communicating. Temporarily disable the firewall app and check whether things improve; if that's the cause, review and adjust the relevant rule.
macOS Updates and Known Bugs
Wi-Fi-related bugs are sometimes reported right after a major macOS update. Conversely, updates can also fix existing bugs.
Check for and apply updates
- Open System Settings → General → Software Update.
- If an update is available, click "Update Now" to apply it.
If a problem started after an update, searching Apple's support pages or Apple Discussions for "macOS [version] Wi-Fi" will often turn up reports of the same issue along with workarounds.
SMC / NVRAM reset (Intel Macs only)
Apple Silicon Macs (M1/M2/M3/M4) do not have a manual SMC or NVRAM reset procedure. Holding the power button to force a restart performs an equivalent operation. The following steps are for Intel Macs only.
SMC reset (Intel Mac without T2 chip):
- Shut down the Mac.
- With the AC adapter connected, hold Left Shift + Left Ctrl + Left Option + Power button simultaneously for 10 seconds.
- Release all keys, then press the power button to start normally.
SMC reset (Intel Mac with T2 chip — MacBook Air 2018–2020, MacBook Pro 2018–2020, etc.):
- Shut down the Mac.
- Hold Right Shift + Left Ctrl + Left Option, then add the Power button and hold all four keys together for 7 seconds.
- Release all keys, wait a few seconds, then press the power button to start normally.
NVRAM reset (Intel Mac):
- Shut down the Mac.
- Press the power button and immediately hold Cmd + Option + P + R simultaneously.
- Keep holding until the startup chime sounds twice (or the Apple logo appears twice), then release.
After an NVRAM reset, some settings (time zone, volume, startup disk, etc.) revert to defaults, so you may need to reconfigure them under System Settings → General.
Work / School Wi-Fi (WPA2 Enterprise / 802.1X)
Unlike home Wi-Fi, enterprise and university networks often use WPA2 Enterprise (802.1X authentication), which requires a per-user ID and password or a digital certificate. If the configuration isn't exactly right, you won't be able to connect.
Check the certificate (profile)
An expired MDM (Mobile Device Management) profile or certificate distributed by your employer or school will prevent you from connecting.
- Open System Settings → General → Device Management.
- Review the list of installed profiles.
- Check whether any profile related to Wi-Fi settings is marked as "Expired."
- If a profile has expired, contact your IT department or school's IT support to request a new one.
Remove old certificates from Keychain Access
Old certificates saved during a previous connection can conflict with newer ones.
- Use Spotlight (Cmd + Space) to search for "Keychain Access" and open it.
- Select "login" from the left sidebar.
- In the search bar at the top, enter your work/school Wi-Fi name or domain name.
- Select any old certificates or password entries found and press the Delete key to remove them.
- Try connecting to the Wi-Fi again (you'll be prompted to re-enter your credentials).
Before deleting, taking a screenshot for reference is a good idea — if you accidentally delete something important, you'll have a record of what was there.
When Hardware Failure Is Suspected
If you've tried everything above and nothing works, a physical failure of the Mac's built-in Wi-Fi card or antenna may be to blame.
Signs of a failed internal Wi-Fi card
If multiple items below apply, there's a good chance it's a hardware failure.
- The Wi-Fi toggle is grayed out and can't be turned on or off in System Settings.
- The Wi-Fi icon in the menu bar shows a "!" continuously.
- An error says "Wi-Fi: No hardware installed."
- Wireless Diagnostics doesn't detect any Wi-Fi interface.
- The problem started after a physical shock, such as a drop or liquid spill.
On Apple Silicon Macs, the Wi-Fi chip is soldered directly to the logic board and cannot be replaced by the user. On some Intel Mac models it is technically replaceable, but requires Apple-certified parts and specialized skills.
When to visit Apple Support / Genius Bar
If the signs above are present, software fixes are unlikely to help.
- Book an appointment at an Apple Store (Genius Bar) via the Apple Support app or getsupport.apple.com.
- Apple Authorized Service Providers can also diagnose and repair your Mac.
- Back up your data with Time Machine or another method before bringing your Mac in.
If you have AppleCare+, accidental damage is partially covered. Some models may also qualify for an out-of-warranty repair program for specific known issues — check the Apple Support page with your Mac's model and symptom. For Mac troubleshooting in general, see the Mac Troubleshooting Guide | Fixes Organized by Symptom.
Summary: Troubleshooting Checklist in Order
Here's the recommended order for tackling Mac Wi-Fi problems.
- Identify your symptom (SSID not showing / password rejected / no internet / slow speed / drops after sleep / only one network fails).
- Toggle Wi-Fi off/on → restart macOS → check for Airplane Mode.
- Use "Forget This Network" to delete and re-register the Wi-Fi entry.
- Test on another device to determine whether the issue is on the Mac side or the router/ISP side.
- Restart the router (30 seconds with power off).
- Try switching between the 5 GHz and 2.4 GHz bands.
- Change DNS to Cloudflare (1.1.1.1) or Google (8.8.8.8).
- Temporarily disable VPN, proxy, and firewall software.
- Run Wireless Diagnostics to identify the problem.
- Move the plist files to regenerate the network configuration.
- Intel Macs only: try an SMC reset or NVRAM reset.
- For work/school Wi-Fi: check the validity of profiles and certificates.
- If hardware failure signs are present, visit the Genius Bar.
Most cases are resolved somewhere between steps 2 and 6. If your iPhone is having the same problem, check out How to Fix an iPhone That Won't Connect to Wi-Fi | Troubleshooting by Symptom as well.
