The short answer
If every other device connects, the router is fine and the problem is on the phone. Forget the network, restart the phone, and rejoin. If that fails, reset the phone’s network settings — that clears the corrupted Wi-Fi profile that causes most of these cases. Check that MAC address randomisation is not being blocked by your router.
This is one of the few faults where you can be confident about the cause before you start. Other devices connect to the same network without complaint, so the router is broadcasting correctly, the password is right and the internet is up. Everything that follows is about the phone.
Read the error, because it narrows things immediately
The exact message tells you a lot:
- “Incorrect password” or “Authentication error” — the phone has a stale saved profile, or the router is rejecting it. Forget and rejoin.
- “Obtaining IP address” that never finishes — DHCP. The router is not handing the phone an address, often because the lease pool is full or MAC filtering is on.
- “Connected, no internet” — the phone has joined the network successfully. This is a DNS or gateway problem, not a Wi-Fi problem.
- “Connected” but nothing loads, only on this phone — look at DNS, a VPN, or a private DNS setting.
- The network does not appear in the list at all — band or channel. The phone may not see a 5 GHz network on certain channels, or the SSID is hidden.
The fixes, in order
Toggle aeroplane mode
Turn aeroplane mode on, wait ten seconds, turn it off. This resets every radio in the phone including Wi-Fi, and it takes five seconds. It resolves a surprising number of temporary association failures.
Forget the network and rejoin
On iPhone: Settings, Wi-Fi, tap the i next to the network, Forget This Network. On Android: Settings, Network and internet, Internet, tap the gear next to the network, Forget. Restart the phone before rejoining — that order matters, because it clears the profile from memory as well as from storage. Then reconnect and type the password carefully.
Check MAC address randomisation
Both iOS and Android now present a different, randomised hardware address to each network for privacy. If your router uses MAC filtering or a guest access list, the randomised address is not on the approved list and the phone is refused. On iPhone: Settings, Wi-Fi, tap the i, and turn off Private Wi-Fi Address. On Android: the network’s settings, Privacy, then Use device MAC. Only do this on networks you trust — it is a privacy feature and worth keeping on elsewhere.
Reset network settings
This is the step that fixes most stubborn cases. It clears every saved Wi-Fi network, Bluetooth pairing and VPN or APN configuration, and rebuilds them from scratch. On iPhone: Settings, General, Transfer or Reset iPhone, Reset, Reset Network Settings. On Android: Settings, System, Reset options, Reset Wi-Fi, mobile and Bluetooth. You will need your Wi-Fi passwords again afterwards, so have them to hand.
Turn off VPNs, private DNS and content blockers
A VPN profile, a Private DNS entry or a DNS-based ad blocker will make a perfectly connected phone look like it has no internet. On Android, check Settings, Network and internet, Private DNS and set it to Off or Automatic to test. On iPhone, check Settings, General, VPN and Device Management.
Check the router is not full or filtering
Log into the router and look at the connected devices list. Two things to check: whether MAC filtering or access control is switched on, and whether the DHCP pool has run out of addresses. Older routers default to a small pool, and a house full of smart devices can exhaust it — at which point the newest device to ask gets nothing.
Try the other band
If your router broadcasts 2.4 GHz and 5 GHz under separate names, try the other one. A phone that joins 2.4 GHz but not 5 GHz points at a channel problem: some routers use channels that phones sold in other regions will not connect to. In the router’s 5 GHz settings, set the channel to a low one such as 36, 40, 44 or 48 and try again.
Turn on the mobile hotspot on a second phone and try to join it with the problem phone. If it connects to the hotspot without trouble, the phone’s Wi-Fi hardware is fine and the issue is specific to your network profile or your router’s settings.
If it says connected but nothing loads
This is a different fault and deserves different steps. The phone has associated with the router; the traffic is not getting through. Work through:
- Set DNS manually. Change the phone’s DNS for that network to 1.1.1.1 or 8.8.8.8 and retest. If pages load, your router’s DNS was the problem.
- Check the date and time. A clock that is badly wrong breaks certificate validation, and every secure site fails while the connection itself is fine. Set it to automatic.
- Look for a captive portal. On guest and public networks, a sign-in page must be accepted first. Try opening a plain http address, which forces the portal to appear.
When it is the phone’s hardware
Genuine Wi-Fi hardware failure is uncommon, but it happens after drops and water exposure. The signs are consistent: the phone cannot see any network anywhere, or the Wi-Fi toggle switches itself back off, or signal is extremely weak when standing next to the router. If a network settings reset changes nothing and the phone will not join a hotspot either, it is worth a service centre.
Frequently asked questions
Nearly always a stale saved profile rather than a genuinely wrong password. Forget the network, restart the phone, then rejoin. It can also happen if the router’s security mode was recently changed, for example from WPA2 to WPA3, which some older phones handle badly.Why does my phone say incorrect password when the password is right?
Saved Wi-Fi networks and their passwords, Bluetooth pairings, VPN configurations and mobile network settings. It does not touch your apps, photos, messages or accounts. Have your Wi-Fi password ready before you do it.What does resetting network settings actually delete?
Usually the channel. Routers can use 5 GHz channels that are restricted in some regions, and a phone bought elsewhere will not display them. Setting the router to a low channel such as 36 or 44 makes the network visible to almost everything.Why can my phone see the 2.4 GHz network but not the 5 GHz one?
No. Leave it on everywhere except your own home network, and only turn it off there if your router uses MAC filtering. It exists to stop networks tracking your device across locations, which is worth keeping.Should I turn off private Wi-Fi address permanently?
Forget, restart, rejoin. If that fails, reset network settings — between them they resolve the overwhelming majority of single-phone Wi-Fi failures.
