A WiFi adapter that suddenly stops working is one of the more frustrating PC problems because it cuts you off from the obvious fix: looking up the answer online. The symptoms vary – sometimes WiFi disappears from the system tray entirely, sometimes it shows but won’t connect, sometimes it connects but no traffic flows. Each variation points to different causes. Here’s the practical troubleshooting order that resolves most cases without buying replacement hardware.
First five-minute checks
Before opening Device Manager or thinking about drivers, rule out the obvious stuff. These three checks solve a surprising number of “WiFi not working” cases.
Toggle airplane mode off and back on. Sounds dumb. Works often. The Windows airplane mode toggle resets your WiFi radio at the firmware level, which can clear minor glitches without a full reboot.
Check if WiFi is enabled on your laptop’s physical switch or function key. Many laptops have a Fn+F2 or Fn+F12 shortcut that toggles WiFi on and off. It’s easy to hit accidentally while typing. Look at the WiFi icon on the relevant function key – if it has an LED, see whether the LED is lit.
Reboot the router. Unplug it from power for 30 seconds, plug it back in, wait 2 minutes for it to fully boot. Router glitches can manifest as “my PC’s WiFi isn’t working” even when the PC is fine.
Check Device Manager
Right-click Start > Device Manager. Expand “Network adapters.” You should see your WiFi adapter listed (often with “Wireless” or “Wi-Fi” in the name).
If the adapter has a yellow warning triangle, there’s a driver problem. Right-click it > Properties > Driver tab. Try “Roll Back Driver” first if the option is available – if WiFi worked yesterday and stopped today, a recent driver update is the likely culprit. If roll back isn’t available, click “Update Driver” > “Search automatically for drivers.”
If the adapter doesn’t appear in Network adapters at all, look in the “Other devices” section. An adapter listed there with a yellow triangle means Windows can’t identify it – you’ll need to manually install the driver from your laptop or motherboard manufacturer‘s website.
If you don’t see the adapter anywhere in Device Manager (not even with hidden devices enabled), the adapter might be physically disabled in BIOS or has a hardware failure. Check BIOS first since it’s the easier fix.
Reset the network stack
Windows has a complete network stack reset command that resolves many WiFi issues without requiring uninstalls or reinstalls.
Open Settings > Network & Internet > Advanced network settings > Network reset. Click “Reset now.” Confirm the prompt. Windows will restart in 5 minutes and reinstall all network adapters and reset all networking settings to factory defaults.
After the reboot, you’ll need to reconnect to your WiFi network and re-enter the password. You’ll also lose any VPN configurations, network profiles, and custom adapter settings. The trade-off: this fixes about 80% of stubborn networking issues without any deeper troubleshooting.
If you prefer a less destructive approach, open Command Prompt as Administrator and run these in order: “netsh winsock reset”, “netsh int ip reset”, “ipconfig /release”, “ipconfig /renew”, “ipconfig /flushdns”. Then reboot. This resets TCP/IP stack and DNS cache without wiping adapter settings.
Reinstall the WiFi driver
If basic Windows tools haven’t worked, a clean driver reinstall often does. The trick is doing it properly, not just hitting “Update Driver” again.
First, download the latest WiFi driver from your laptop or motherboard manufacturer’s support page. Save it to a USB drive or a local folder. You need this before uninstalling because once the driver is gone, you can’t download a replacement without internet.
In Device Manager, right-click your WiFi adapter > Uninstall device. Check “Delete the driver software for this device” if the option appears. Click Uninstall. Reboot.
On reboot, Windows will try to reinstall a generic driver. If that fails or doesn’t fix the issue, manually install the driver you downloaded by running the installer.
External USB WiFi adapter as bypass
If you’ve tried everything and your internal WiFi still doesn’t work, an external USB WiFi adapter is a fast bypass that costs $15-30 and avoids needing internal repairs. Plug it into a USB port, install drivers if Windows doesn’t auto-detect, connect to your network. Done.
These external adapters work especially well for desktop PCs where the internal WiFi adapter is on the motherboard and would require disassembly to repair. For laptops, the M.2 WiFi card can usually be replaced if you’re comfortable with internal repairs (often $20-40 for the replacement card), but an external dongle is simpler.
Look for adapters supporting WiFi 6 (802.11ax) or WiFi 6E for best speeds. Older WiFi 5 (802.11ac) adapters still work but max out around 800Mbps real-world throughput.
Check power management settings
Windows aggressively powers down WiFi adapters to save battery on laptops, which sometimes causes WiFi to drop randomly or fail to wake from sleep. This is often the culprit when WiFi works fine for a while then stops, or doesn’t reconnect after the laptop sleeps.
Open Device Manager > Network adapters > right-click WiFi adapter > Properties > Power Management tab. Uncheck “Allow the computer to turn off this device to save power.” Click OK.
Also check Settings > System > Power & battery > Power mode. Set to “Best performance” temporarily and see if WiFi stability improves.
Router compatibility issues
Sometimes the issue isn’t your adapter – it’s how it talks to your specific router. Two settings on the router side commonly cause adapter compatibility problems.
First, check the WiFi channel. If multiple neighbors are using the same channel (especially channel 6 or channel 11 on 2.4 GHz), interference can prevent connection. Log into your router and change to a less crowded channel. Tools like WiFi Analyzer can show you which channels are busy in your area.
Second, check the wireless security mode. Some older WiFi adapters can’t handle WPA3 properly. Try switching the router to WPA2-Personal temporarily and see if the adapter connects. If yes, you’ve identified the issue – either keep WPA2 (less secure but works) or upgrade your adapter.
Common questions
Why does my WiFi suddenly stop working after a Windows update?
Windows updates occasionally ship problematic WiFi drivers. Roll back the WiFi driver in Device Manager (right-click adapter > Properties > Driver tab > Roll Back Driver) or uninstall the most recent Windows update. Microsoft usually pushes a fix within a few weeks. In the meantime, you can pause Windows Updates to prevent the problematic driver from reinstalling.
My WiFi shows the network but won’t connect – why?
If you can see networks but can’t connect, the most common causes are wrong password (try forgetting and re-adding the network), DHCP issues on the router (reboot the router), MAC address filtering enabled on the router (disable it temporarily), or a corrupt network profile (delete and recreate). Run the Network Troubleshooter from Settings > System > Troubleshoot > Other troubleshooters.
Do I need to buy a new WiFi adapter?
Usually no. Most WiFi problems are software or settings issues, not hardware failure. Work through driver reinstalls, network resets, and power management settings before assuming the adapter is dead. If you’ve exhausted those options and an external USB adapter works fine, then yes – your internal adapter has likely failed and replacement makes sense.
Why is my WiFi slow only on this PC?
Multiple causes possible: outdated driver, WiFi adapter only supports older standards (802.11n caps around 100Mbps real-world), too far from router, interference from other devices, or background processes hogging bandwidth. Check your adapter’s spec – if it’s WiFi 5 or WiFi 6 capable but you’re getting WiFi 4 speeds, the driver or router setting is limiting you. Update the driver and verify the router is broadcasting on 5 GHz or 6 GHz bands, not just 2.4 GHz.
