> ## Documentation Index > Fetch the complete documentation index at: https://docs.derekdinh.com/llms.txt > Use this file to discover all available pages before exploring further. # Step-by-Step Wi-Fi Troubleshooting for Common Issues > Resolve Wi-Fi connection failures, poor speeds, and DHCP errors by following this structured guide covering drivers, bands, interference, and TCP/IP reset. Wi-Fi problems range from a device that simply will not see a network to one that connects but drops frequently or delivers only a fraction of the expected speed. Because wireless networking involves hardware, drivers, radio frequencies, and network configuration all at once, a structured diagnostic approach prevents you from chasing symptoms in the wrong layer. Work through the steps below in order — most issues are resolved before you reach the end. A corrupted or outdated saved network profile is one of the most common causes of Wi-Fi failures that appear after an OS update, a router reconfiguration, or a password change. Removing the saved profile and reconnecting from scratch forces your device to negotiate a clean session. **Windows:** 1. Click the **Wi-Fi icon** in the taskbar. 2. Click the **arrow (>)** next to your network name to expand it. 3. Click **Forget**. 4. Click the network name again, enter the password, and click **Connect**. Alternatively, use the command line to manage saved profiles: ```powershell theme={null} # List all saved Wi-Fi profiles netsh wlan show profiles # Forget a specific network (replace 'MyNetwork' with your SSID) netsh wlan delete profile name="MyNetwork" # Reconnect (Windows will prompt for password via the taskbar icon) netsh wlan connect name="MyNetwork" ``` **macOS:** 1. Hold **Option** and click the **Wi-Fi menu bar icon**, then click **Wi-Fi Settings** (or go to **System Settings → Network → Wi-Fi**). 2. Click **Advanced** (or the **Details** button next to your network if already connected). 3. Locate the network in the saved networks list and click the **minus (–)** button, then click **Remove**. 4. Reconnect by selecting the network from the menu bar Wi-Fi icon and entering the password. If you recently changed your Wi-Fi password on the router but your device still shows as "connected," it may be using a cached session. Forgetting the network forces it to use the new password. An outdated or corrupted wireless driver is a frequent cause of random disconnections, slow speeds, and networks not appearing in the scan list — particularly after a major Windows update. **Windows — Device Manager:** 1. Press **Win + X** and select **Device Manager**. 2. Expand **Network Adapters**. 3. Right-click your wireless adapter (typically named something like **Intel Wi-Fi 6 AX201** or **Realtek 8822CE**) and choose **Update driver**. 4. Select **Search automatically for drivers** to let Windows check for a newer driver. 5. If Windows reports it is up to date, visit the laptop or motherboard manufacturer's support website directly — manufacturer-specific driver packages often outpace what Windows Update provides. You can also check your current driver version and date via PowerShell: ```powershell theme={null} Get-WmiObject Win32_NetworkAdapter | Where-Object { $_.Name -like "*Wi-Fi*" -or $_.Name -like "*Wireless*" } | Select-Object Name, DriverVersion, DriverDate ``` **Rolling back a driver (if Wi-Fi broke after a recent update):** 1. In Device Manager, right-click the wireless adapter → **Properties**. 2. Go to the **Driver** tab and click **Roll Back Driver**. 3. Follow the prompts and restart when prompted. **macOS:** Wi-Fi drivers on macOS are bundled with the operating system and cannot be updated independently. If you are experiencing driver-level issues, check for a pending macOS update: **System Settings → General → Software Update**. After updating or rolling back a driver, always restart your computer before testing. The new driver is not fully active until the OS has performed a clean boot. Modern dual-band and tri-band routers broadcast on both 2.4 GHz and 5 GHz simultaneously, often under different network names (SSIDs). Connecting to the wrong band can cause exactly the symptoms you are troubleshooting. | Band | Range | Speed | Interference | | ----------- | -------------------------------------- | ------------------------------------- | ---------------------------------------------------------------------- | | **2.4 GHz** | Long (better through walls) | Lower (up to \~300 Mbps in practice) | High (shares spectrum with microwaves, baby monitors, older Bluetooth) | | **5 GHz** | Short (degrades quickly through walls) | Higher (up to \~1.3 Gbps in practice) | Low (less congested spectrum) | **Best practice guidance:** * Use **5 GHz** when you are in the same room as the router or within one wall's distance. You will get significantly faster and more stable performance. * Use **2.4 GHz** when you are far from the router or separated by multiple walls and floors, where the stronger penetration of the lower frequency outweighs its speed disadvantage. * If your router broadcasts a single combined SSID (band steering), your device automatically picks a band. You can force a specific band by connecting to separate SSIDs if your router supports them (e.g., `HomeNetwork` vs. `HomeNetwork_5G`). **Check which band you are currently connected to on Windows:** ```powershell theme={null} netsh wlan show interfaces ``` Look for the **Radio type** field. Values like `802.11ac` or `802.11ax` confirm a 5 GHz connection; `802.11g` or `802.11n` alone may indicate 2.4 GHz. **Check on macOS:** Hold **Option** and click the **Wi-Fi menu bar icon**. The pop-up shows the channel number. Channels 1–13 are 2.4 GHz; channels 36 and above are 5 GHz. If your router uses the same SSID for both bands, you can force your device to the preferred band by temporarily disabling the other band in the router's admin interface, connecting your device, then re-enabling the disabled band. Radio interference from other devices and networks degrades Wi-Fi performance without producing any obvious error message. The connection appears healthy but delivers poor throughput and high latency. **Common sources of 2.4 GHz interference:** * Microwave ovens (avoid using the microwave while on a video call) * Baby monitors and wireless cameras * Cordless phones operating at 2.4 GHz * Neighboring Wi-Fi networks on overlapping channels * Older Bluetooth peripherals **Steps to reduce interference:** 1. **Change the router's Wi-Fi channel.** Log into your router's admin page and navigate to the wireless settings. For 2.4 GHz, non-overlapping channels are **1, 6, and 11**. For 5 GHz, most channels are non-overlapping. Use a Wi-Fi analyzer app to see which channels neighboring networks are using and pick the least crowded one. ```bash theme={null} # macOS — scan for nearby networks and their channels /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -s ``` ```powershell theme={null} # Windows — list nearby networks (channel info visible in full output) netsh wlan show networks mode=bssid ``` 2. **Reposition the router.** Place it in a central location, elevated off the floor, away from microwaves, cordless phone bases, and large metal objects such as filing cabinets. 3. **Enable "Auto Channel" on the router** if available. Modern routers can scan for the least congested channel on startup and after reboot. 4. **Separate IoT devices onto the 2.4 GHz band** and use 5 GHz exclusively for computers and phones, reducing channel congestion for your primary devices. In dense office environments with many overlapping networks, even a perfect channel selection may not eliminate all interference. In these cases, a wired Ethernet connection is the most reliable long-term solution. Refer to the [Slow Network](/networking/slow-network) guide for wired connection steps. When your device connects to Wi-Fi, the router's DHCP server assigns it an IP address for a set lease period. A stale or conflicting lease can cause connection failures, limited connectivity warnings, or inability to reach the gateway. **Windows — Release and Renew DHCP Lease:** Open **Command Prompt** or **PowerShell** as Administrator and run: ```powershell theme={null} # Release the current IP address ipconfig /release # Pause briefly, then request a new lease ipconfig /renew ``` Confirm the result: ```powershell theme={null} ipconfig /all ``` You should see a valid IP address (starting with `10.`, `172.16.`–`172.31.`, or `192.168.`) with a populated **Default Gateway** and **DNS Servers** field. An address of `169.254.x.x` means the DHCP renewal failed and your device cannot reach the DHCP server. **macOS:** 1. Open **System Settings → Network → Wi-Fi → Details → TCP/IP**. 2. Click **Renew DHCP Lease** and wait a few seconds for the new lease to populate. Or via Terminal: ```bash theme={null} # Replace en0 with your Wi-Fi interface name (check with: networksetup -listallhardwareports) sudo ipconfig set en0 DHCP ``` Running `ipconfig /release` on Windows immediately drops your IP address and terminates any active network connections. Close remote desktop sessions, save open files that depend on network paths, and complete any uploads or downloads before running this command. If your network adapter shows as connected but you still cannot reach the internet — and DHCP renewal did not help — the underlying TCP/IP networking stack may be corrupted. This can happen after a failed OS update, malware removal, or VPN client uninstallation. **Windows — Full TCP/IP and Winsock Reset:** Run **Command Prompt as Administrator** and execute the following commands in order: ```powershell theme={null} # Reset TCP/IP stack to factory defaults netsh int ip reset # Reset Winsock catalog (fixes corrupted socket configurations) netsh winsock reset # Flush DNS cache ipconfig /flushdns # Release and renew IP address ipconfig /release ipconfig /renew ``` **Restart your computer after running all four commands.** The TCP/IP reset writes changes to the registry that only take full effect after a reboot. After restarting, verify your connection: ```powershell theme={null} # Confirm TCP/IP stack is healthy netsh int ip show config # Test connectivity ping 8.8.8.8 ping google.com ``` **macOS — Remove and Re-add the Wi-Fi Interface:** 1. Go to **System Settings → Network**. 2. Select **Wi-Fi** and click the **minus (–)** button at the bottom of the interface list to remove it. 3. Click the **plus (+)** button, select **Wi-Fi** as the interface type, and click **Create**. 4. Reconnect to your network. Alternatively, delete the stored Wi-Fi preferences file and let macOS rebuild it: ```bash theme={null} # Back up, then remove the Wi-Fi preference files (requires admin password) sudo cp /Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist ~/Desktop/airport-backup.plist sudo rm /Library/Preferences/SystemConfiguration/com.apple.airport.preferences.plist sudo rm /Library/Preferences/SystemConfiguration/NetworkInterfaces.plist ``` Restart your Mac after removing these files. macOS will recreate them automatically. Deleting the macOS Wi-Fi preferences file removes all saved Wi-Fi network passwords from the system. Make sure you have your Wi-Fi password available before proceeding, as your Mac will prompt for it on the next connection. If you have worked through all of the above steps and the Wi-Fi problem persists, the issue may involve defective hardware, a deeper driver problem, or a network infrastructure fault that requires hands-on support. * **Wireless adapter name and driver version:** ```powershell theme={null} # Windows netsh wlan show drivers ``` * **Current connection details (band, channel, signal strength, BSSID):** ```powershell theme={null} # Windows netsh wlan show interfaces ``` ```bash theme={null} # macOS (hold Option + click Wi-Fi icon in menu bar) ``` * **Full output of `ipconfig /all`** (Windows) or `ifconfig` (macOS) at the time of the failure * **Event Viewer errors** (Windows): Open Event Viewer → **Windows Logs → System**, filter by **Source: WLAN-AutoConfig**, and note any warnings or errors * **Whether the issue is reproducible on the same device on a different network** — if it works on a mobile hotspot but not the office network, the problem is network infrastructure, not the device * **Whether other devices on the same network have the same problem** — if yes, it is a router/AP issue; if no, it is specific to your device * **OS version and date of last update** * **Make, model, and age of your device** — hardware faults (e.g., a failing wireless card) are more common on devices over four years old If your device consistently drops Wi-Fi after a period of inactivity, check the **Power Management** settings for your wireless adapter in Device Manager (Windows). Right-click the adapter → **Properties → Power Management** and uncheck **Allow the computer to turn off this device to save power**. This is a common culprit on laptops that disappears from sleep.