Wi-Fi password is correct but won't connect – real fix

Quick answer for advanced users

Delete the saved network profile from your device's Wi-Fi settings, then re-add it. If that fails, flush the ARP cache with arp -d * (Windows) or sudo arp -a -d (macOS), then restart the router. The root cause is almost always a corrupted saved profile or a stale DHCP/ARP entry, not a password typo.

Why this happens

What's actually happening here is that your device stores more than just the password when you connect to a Wi-Fi network. It also saves the DHCP lease (the IP address the router gave you), the DNS server assignments, and sometimes a cached ARP entry mapping that IP to the router's MAC address. When any of these cached items get stale or corrupted — say, your router rebooted overnight, or you connected to a guest network with the same SSID — your device tries to reuse the old data, but the router rejects it. The authentication dialog shows the password field as filled, and you might even see “Saved” or “Connected” briefly before it drops back to “No Internet” or loops endlessly.

Another common trigger: you upgraded your router firmware or changed its admin password, which reset the DHCP server state. Now your phone is trying to renew an IP address that belongs to a different device, or the router thinks your MAC address is already leased to someone else. The password check passes (WPA2/3 handshake succeeds), but the DHCP negotiation fails, so you get stuck at “Obtaining IP address” forever.

On corporate or university networks, the problem is often an expired certificate or a cached RADIUS session. But for home networks, it's almost always the saved profile or a DHCP/ARP stale entry.

Fix steps (try in order)

1. Forget the network completely. On Windows 11: Settings > Network & Internet > Wi-Fi > Manage known networks, click the network name, select Forget. On macOS: System Settings > Wi-Fi > click Details next to the network, then Forget This Network. On Android: Settings > Network & Internet > Wi-Fi > tap the saved network, then Forget. On iOS: Settings > Wi-Fi > tap the blue info icon, then Forget This Network. This removes the corrupted profile.
2. Restart your device. A full power cycle clears the ARP cache and resets the network stack. On Windows, run ipconfig /flushdns and arp -d * from an admin command prompt instead of just rebooting if you want to be surgical.
3. Reconnect to the network. Select the SSID, type the password fresh. This forces a new DHCP handshake. If it connects but shows “No Internet” after 10 seconds, move to step 4.
4. Restart the router. Unplug the power for 30 seconds. This clears the router's DHCP lease table and ARP cache. When it boots back up, your device will get a fresh lease. This is the single most effective step if you've already forgotten and re-added the network.
5. Assign a static IP (fallback). If DHCP still fails, manually set an IP address on your device that's outside the router's DHCP pool but within the same subnet. For example, if your router's IP is 192.168.1.1 and the DHCP pool is 192.168.1.100–200, set your device to 192.168.1.50 with subnet mask 255.255.255.0 and default gateway 192.168.1.1. This bypasses DHCP entirely.

Alternative fixes if the main one fails

• Change the Wi-Fi channel. If your router is on a congested channel (like channel 6 on 2.4 GHz), the handshake can time out. Log into your router admin page and switch to channel 1 or 11 (2.4 GHz) or a less crowded 5 GHz channel. This isn't about signal strength — it's about packet loss during the 4-way handshake.
• Update your Wi-Fi adapter driver. On Windows, outdated drivers (especially Realtek and Broadcom) have known bugs where the WPA2 handshake succeeds but the driver hangs at the 4-way handshake completion. Check your manufacturer's site, not Windows Update.
• Disable Wi-Fi 6 (802.11ax) on the router. Some older clients (Android 10 and earlier, some IoT devices) have compatibility issues with OFDMA and fail the DHCP after authentication. Temporarily disable Wi-Fi 6 mode in router settings to test.
• Check MAC address filtering. If your router has MAC filtering enabled, and you recently changed your device (or its MAC), add the new MAC to the allowed list. This is rare but catches people who replace a phone or laptop.

Prevention tip

The easiest way to avoid this headache is to not let your device auto-connect to networks you rarely use. Every time you join a public or guest Wi-Fi, the profile gets saved. When the router's DHCP pool resets (which happens on any reboot or firmware update), your device tries to renew a stale lease and fails. I delete saved networks I don't use monthly. On your home network, set a DHCP reservation for your primary devices (phone, laptop, desktop) so they always get the same IP. This eliminates the stale lease problem entirely. Most routers call this “Address Reservation” in the DHCP settings.

Also, if you change your Wi-Fi password, always forget the network on every device before typing the new one. Don't just update the password in the saved profile — that rarely works cleanly because the underlying authentication keys are derived from the old password and stored differently. Forget it, re-add it.