Mac Wi-Fi problems range from simple (wrong password) to complex (corrupted network preferences). This guide covers the full range of fixes.

Quick Fixes (Try These First)

  1. Turn Wi-Fi off, wait 10 seconds, turn back on.
  2. Restart your Mac.
  3. Restart your router (unplug 30 seconds).
  4. Move closer to the router.

Medium Fixes

  1. Forget and rejoin network: System Settings > Wi-Fi > (i) next to network > Forget Network. Reconnect and re-enter password.
  2. Renew DHCP lease: System Settings > Network > Wi-Fi > Details > TCP/IP > Renew DHCP Lease.
  3. Change DNS servers: System Settings > Network > Wi-Fi > Details > DNS > Add 1.1.1.1 and 8.8.8.8.
  4. Flush DNS cache: sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
  5. Disable VPN and proxy: VPNs can interfere. Disconnect your VPN and check System Settings > Network > Proxies (should all be unchecked).

Advanced Fixes

  1. Reset network preferences: Delete these files (requires admin, Mac will recreate them on restart):
    /Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist
    /Library/Preferences/SystemConfiguration/com.apple.network.identification.plist
    /Library/Preferences/SystemConfiguration/NetworkInterfaces.plist
  2. Run Wireless Diagnostics: Hold Option key, click Wi-Fi icon, "Open Wireless Diagnostics." Provides automated analysis and log capture.
  3. Check for interference: Wireless Diagnostics > Window > Scan to see nearby networks and channel congestion. Change your router to a less congested channel.

People Also Ask

How do I reset the Wi-Fi on a Mac?
The quickest reset is to forget the network and delete network preferences files. For a full network stack reset, use the Network Reset option under System Settings > General > Transfer or Reset > Reset Network Settings (macOS Sequoia and later).

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