Why One Device Connects to Wi-Fi and Another Doesn't: A Complete Diagnosis

One device - for example, iPhone 14 or Redmi Note 12 — connects to Wi-Fi without problems, and the second (say, MacBook 2017 or Xiaomi Mi Band 5) doesn't detect the network, displays an "Incorrect Password" error, or endlessly "gets IP." This problem occurs even if the router is working and the internet is stable on other devices, and in 4 out of 5 cases, it's caused by incompatible security settings, outdated software, or channel conflicts. To fix the problem in a few minutes, first check three key points: whether the device supports the current Wi-Fi standard (5 GHz or 6 GHz), whether the antivirus software is blocking the network, and whether the encryption settings on the router and client match.

In this article we will look at all possible reasons — from the banal (Wi-Fi turned off on the device) to the exotic (standards conflict 802.11n/ac/ax). We will also provide checklists for diagnostics on Windows, Android, iOS And macOS, a compatibility table of devices with different encryption types, and answers to frequently asked questions. If you've already tried rebooting your router, skip the first section and proceed to hardware conflicts or software failures.

Spoiler: 30% of the time he's to blame not the router, but the "problematic" device itself — especially if it's older than 5 years. But first things first.

Step 1: Basic Check - What to Do First

Before digging deep, rule out the obvious causes. Here minimum checklist, which will save you an hour of time:

Check if Wi-Fi is enabled on the affected device (indicator in the notification bar)

Make sure your device is not in Airplane mode.

Reboot your router (turn off the power for 30 seconds)

Try connecting to a different network (such as a mobile hotspot)

Check if your VPN or antivirus is blocking the connection-->

If at least one item from the list is not completed - do not read further, do this first. In 50% of cases, the problem is solved at this stage. For example, Windows 10/11 Wi-Fi can be turned off using the keys Fn + F2 (on some laptops), and on iPhone - due to accidentally activated mode Low Power Mode (battery saving).

Another simple test: try connecting the “problem” device to another network (A neighbor's, a cafe, a mobile hotspot). If it connects, your router or its settings are to blame. If not, the problem is with the device itself (drivers, hardware failure, MAC address blocking).

⚠️ Attention: If you have dual-band router (2.4 GHz + 5 GHz), try connecting to both bands separately. Older devices (e.g. iPhone 5s or Samsung Galaxy S5) may not support 5 GHz.

Step 2: Router Settings - What Could Go Wrong

The router is the first suspect if one device connects but another doesn't. The most common culprits are:

• 🔒 Encryption type: Outdated WEP or TKIP blocks new devices, and modern WPA3 - old ones.
• 📡 Hidden network (SSID): If the network is not broadcast, some devices cannot "see" it without manual input.
• 🔄 MAC address filtering: Your router settings may allow access only to specific devices.
• 📶 Channel and channel width: Automatic channel selection sometimes causes conflicts (for example, channel 12-14 is not supported in the US).
• 🔌 Device limit: On budget routers (for example, TP-Link TL-WR840N) there may be a limit of 10-20 connections.

How to check? Go to your router's control panel (usually at 192.168.0.1 or 192.168.1.1) and pay attention to:

Critical detail: If your router operates in 5 GHz Only mode, devices that do not support this range (e.g., Amazon Kindle or Sony PS3) will not see the network. The solution is to turn it on 2.4 GHz or create a separate network for such gadgets.

⚠️ Attention: Router settings may reset after a firmware update. If the problem occurred after the update, check to see if your security settings have been reset or your password has changed.

Step 3: Hardware Conflicts – When the Hardware is to Blame

If your router is configured correctly, but one device stubbornly refuses to connect, check it. hardware compatibility with your network. Here are typical scenarios:

• 📱 Old smartphones/tablets: Devices before 2015 (eg iPhone 4s or Samsung Galaxy S3) do not support WPA3 and modern standards 802.11ac/ax.
• 💻 Laptops with a faulty Wi-Fi module: Physical damage to the antenna or overheating of the chip (a common problem with Lenovo IdeaPad And HP Pavilion).
• 📺 Smart TV and set-top boxes: Many models (eg LG WebOS (before 2018) do not work with encryption WPA3 or 5 GHz networks.
• 🔌 USB/Wi-Fi adapters: Cheap adapters (eg TP-Link TL-WN725N) may conflict with drivers or routers ASUS/Netgear.

How to diagnose:

1. Check it out device specifications on the manufacturer's website - does it support your network type (for example, 5 GHz or WPA3).
2. Connect the device to a different router (for example, at a cafe or at a friend's place). If the problem persists, the hardware is to blame.
3. For PC/Laptop: Open device Manager (on Windows) and check if there is an exclamation mark next to Network adapter.

How to check the Wi-Fi module on a laptop?

IN Windows click Win + X → Device Manager → Network Adapters. If next to the adapter name (for example, Intel Wi-Fi 6 AX200) there is a yellow triangle - the driver is not working. For macOS open About This Mac → System Report → Network and check the Wi-Fi status.

If you suspect a module malfunction, try connecting it external USB adapter (For example, TP-Link Archer T2U). If the network works with it, the problem is in the native module.

Step 4: Software glitches – drivers, updates, and OS “glitches”

Most often, software problems occur on Windows And Android, less often - on iOS/macOSHere's what to check:

• 🔄 Wi-Fi Drivers: Outdated or corrupted drivers are the number one cause of PC crashes. For example, on Windows 11 driver for Realtek RTL8188EE may conflict with new standards.
• 📱 OS Updates: On Android Below version 8.0 there may be problems with WPA3On . iOS up to 12.0 - with networks 802.11ax.
• 🛡️ Antivirus/VPN: Programs like Kaspersky or NordVPN Sometimes connections to "suspicious" networks are blocked.
• 🗃️ Network cache: On Android And iOS accumulated network data can cause problems (forgetting the network often helps).

Diagnostic instructions:

Update your Wi-Fi driver (on Windows via device Manager)

Launch Network troubleshooting (Right-click on the Wi-Fi icon in the tray)

On Android/iOS: Forget the network → reconnect

Disable your VPN/antivirus for 5 minutes and try connecting again.

Check if the mode is enabled Saving traffic (Windows) or Low Data Mode (iOS)-->

For Windows useful commands in Command line (run as administrator):

netsh wlan show drivers

This command will show if your adapter supports modern standards (look for the lines 802.11n, 802.11ac).

netsh int ip reset

Resets network settings (helps with errors like "No Internet access").

⚠️ Attention: On Android 10+ has a bug where the device does not connect to networks with WPA3, if it was previously connected to the same network with WPA2The solution is to delete the network from the device's memory and reconnect.

Step 5: Router Firmware Update – When an Update Breaks Your Connection

Router firmware can both fix problems and create them. Typical symptoms of broken firmware:

• One device connects, the other does not (often after an update).
• The router periodically freezes or reboots.
• Unknown options appear in the settings (or old ones disappear).

How to check:

1. Go to the router control panel and check the firmware version (section System Tools or Administration).
2. Compare it with the latest stable version on the manufacturer's website (for example, for ASUS RT-AX88U or Xiaomi Mi Router 4A).
3. If the version is out of date, update the firmware. If the problem persists after updates - try rolling back to the previous one.

Important: on routers TP-Link And MikroTik After updating the firmware, sometimes security settings are reset (for example, the encryption type changes to WPA2/WPA3 instead of WPA2). This blocks old devices.

Step 6: External interference - neighbors, microwaves and walls

If the problem occurs intermittently (sometimes it connects, sometimes it doesn’t) - it’s your fault external interference. Sources:

• 📶 Congested channel: In apartment buildings there are channels 2.4 GHz (especially the 6th) are often overloaded.
• 🍳 Household appliances: Microwaves, cordless phones (DECT), baby monitors operate on the frequency 2.4 GHz.
• 🏢 Obstacles: Concrete walls, metal doors, and mirrors weaken the signal.
• 🌩️ Weather: During a thunderstorm or heavy rain, the quality of communication on 5 GHz may worsen.

How to check:

1. Install a Wi-Fi analyzer application on your smartphone (for example, WiFi Analyzer For Android or NetSpot For iOS).
2. Check which channels are being used by neighboring networks. If your channel is overloaded, change it in your router settings.
3. Try temporarily unplugging your microwave or cordless phone - if the connection improves, they are the problem.

Solutions:

• Switch to 5 GHz (if the device supports it).
• Place the router away from the kitchen and household appliances.
• Use Mesh system (For example, TP-Link Deco or Google Nest WiFi), if the obstacle is physical (walls).

Step 7: Exotic Causes - When Nothing Works

If you've read this far, the problem is likely non-standard. Here are some rare, but possible causes:

• 🔗 IPv6 conflict: Some devices (eg Sony PlayStation 4) don't work with IPv6. The solution is to disable it in the router settings.
• 🕒 Time limit: The router may have an access schedule configured (for example, Wi-Fi is turned off at night).
• 📦 Branded protocols: Routers ASUS With AiProtection or Netgear With Armor sometimes "suspicious" devices are blocked.
• 🔄 Petya routers: Cheap routers (for example, Tenda or Mercusys) may “glitch” when connecting more than 15 devices.

Diagnostics:

1. Check it out router logs (chapter System Log or Journal). Look for records of blocks or authentication errors.
2. Turn it off all additional functions router (parental control, guest network, QoS).
3. Try connecting the "problematic" device via Ethernet cable (if possible). If the internet works, the problem is definitely with the Wi-Fi.

FAQ: Frequently Asked Questions

Why does iPhone connect to Wi-Fi but Android doesn't?

Most often it is the fault encryption: iPhone supports WPA3, and many Android-devices (especially based on MediaTek) - no. Solution: in the router settings, select WPA2-PSK (AES).

Also check if it is turned on Android mode Saving traffic or Adaptive Wi-Fi (on Samsung).

My laptop sees Wi-Fi but won't connect—it says "Unable to connect." What should I do?

Reasons:

1. Outdated Wi-Fi driver (update via device Manager).
2. Conflict with antivirus (disable Kaspersky/Avast for 5 minutes).
3. Incorrect IP settings (please set Obtain an IP automatically in the connection properties).

If that doesn't help, create a new connection manually: Control Panel → Network and Internet → Network and Sharing Center → Set up a new connection.

My Smart TV won't connect to Wi-Fi, but my phone does. What's wrong?

Most likely, the TV does not support:

• Modern encryption (WPA3 or AES).
• Range 5 GHz (if the router only works in it).
• Hidden networks (SSID).

Solution: In the router settings, select WPA2-PSK (AES), turn on 2.4 GHz and disable SSID hiding.

Why does one device connect after changing the Wi-Fi password, but another one doesn't?

Possible reasons:

• The old password is saved on the device (click “Forget network”).
• The new password contains special characters (For example, #, @), which are not supported by older devices.
• When changing the password on the router, it accidentally changed encryption type (for example, with WPA2 on WPA3).

Can a virus block a Wi-Fi connection?

Yes, but very rarely. Some viruses (for example, Trojan.Win32.DNSChanger) change DNS settings or block network connections. Signs:

• Wi-Fi connects, but websites don't open.
• IN hosts file (C:\Windows\System32\drivers\etc\hosts) strange entries appeared.
• The antivirus issues warnings about network activity.

Solution: Scan your system Malwarebytes or Dr.Web CureIt.