The situation when a smartphone or tablet based on Android refuses to connect to Wi-Fi is familiar to many users. The device finds the network, you enter the correct password, but instead of the treasured connection icon, a message appears: “Failed to obtain an IP address.” This error means that your gadget was unable to agree with the router on what unique identifier to assign to it on the local network.
Without this digital passport, data exchange is impossible, even if a physical connection is established. The problem may lie either in a software failure of the phone itself or in incorrect router settings. Sometimes the cause is an address conflict or an outdated encryption protocol.
In this article we will examine in detail the mechanics of operation DHCP servers, the causes of failures and step-by-step guide for troubleshooting. You will learn how a static IP can save the situation, and why rebooting the router is not always a panacea.
Connection mechanics: how address distribution works
When you try to connect to a wireless network, your device sends a broadcast request to all available access points. After password authentication, the process of obtaining network settings begins. The protocol DHCP (Dynamic Host Configuration Protocol) is responsible for this procedure. The router acts as a server that issues the client (your phone) a temporary IP address from its pool.
If this process is interrupted, Android cannot complete the connection. The error often occurs at the “Obtaining an IP address” stage. This may happen because the address pool on the router is exhausted, or the response from the server simply does not reach the client due to interference or software filters.
It is important to understand the difference between dynamic and static assignment. By default, all devices operate in DHCPmode, receiving an address automatically every time they connect. However, when the automatic protocol fails, manually setting network parameters often becomes the only working solution.
⚠️ Attention: If you see this error only in one specific network (for example, in a cafe or with friends), the problem is most likely on the side of someone else's router, and not your smartphone.
Primary diagnosis and quick solutions
Before delving into deep settings, it’s worth eliminating basic system glitches. Often a temporary glitch in the Android network stack prevents a correct handshake with the router. First of all, try to forget the network. Go to Wi-Fi settings, select the desired access point and click “Delete network” or “Forget”. After that, connect again, carefully entering the password.
The second effective method is to reboot the network equipment. Unplug the router for 10-15 seconds. This will clear the device's RAM and reset hung DHCP processes. Turn the router back on and wait until the indicators are fully loaded.
Also check if airplane mode is turned on on your phone. Sometimes the system gets stuck in this state and the antenna icon disappears, even if airplane mode is visually turned off. Try activating it manually for 5 seconds and then disabling it.
If rebooting the router does not help, try connecting another device (laptop or friend’s phone) to the same Wi-Fi network. If it also does not receive an IP, the problem is definitely in the router or provider.
Configuring a static IP address manually
If automatically receiving settings does not work, the most reliable way to solve the problem is to manually set the parameters. You need to give the device a permanent address that will not conflict with other gadgets on the network. To do this, go to the advanced settings of your Wi-Fi network.
In the IP settings menu, change the value from DHCP to Static (or Static). Fields for entering numerical values will open in front of you. You must specify the IP address, gateway, network prefix length, and DNS servers. This data can usually be viewed on a sticker under the router or in the settings of any other device that is successfully connected to this network.
A typical configuration for home networks looks like this:
- 📍 IP address: 192.168.1.128 (the last digits can be anything from 2 to 254)
- 🚪 Gateway: 192.168.1.1 (the address of your router)
- 📏 Network prefix length: 24
- 🌐 DNS 1: 8.8.8.8 (Google server)
Make sure that the IP address you select is not occupied by another device. If there are a lot of gadgets on the network, it is better to choose a higher number, for example, 192.168.1.200, to avoid collisions. After entering the data, click “Save” and try to connect.
☑️ Checking data for static IP
Reset network settings on Android
When simple methods do not help, the system may have accumulated network interface configuration errors. Resetting network settings will return all Wi-Fi, Bluetooth and mobile data settings to factory defaults. This will not delete your personal files, photos or applications, but you will have to re-enter passwords for all saved Wi-Fi networks.
The procedure is performed through the settings menu. The path may differ depending on the version Android and shell manufacturer, but usually it looks like this: Settings → System → Reset settings → Reset Wi-Fi, mobile data and Bluetooth settings. On some Samsung models, the path may be Settings → General settings → Reset → Reset network settings.
After confirming the action, the phone will reboot or simply apply changes. Try connecting to the problematic network again. This method is especially effective if you recently updated the firmware or transferred data from an old device, and some configuration files may have become damaged.
| Action | What is being reset | Risk of data loss |
|---|---|---|
| Reset network settings | Wi-Fi passwords, Bluetooth, APN settings | None (photos and contacts are safe) |
| Reset all settings | Everything, including alarms and wallpapers | Minimum (data remains) |
| Hard Reset | Complete removal of all data | High (the phone will be like new) |
⚠️ Attention: Do not confuse “Reset network settings” with “Reset to factory settings” (Hard Reset). The second option will completely delete all your applications, accounts and files from the phone’s internal memory.
Problems on the side of the router and provider
Sometimes the root of evil is hidden not in the phone, but in the router configuration. If a limiting number of devices are connected to the router, it simply cannot issue a new IP address. In the router settings, you can increase the range of the DHCP pool or reduce the address lease time to release occupied IPs faster.
Another common reason is incompatibility of encryption standards. Old devices may not work well with the protocol, while new ones sometimes conflict with outdated ones. Try changing the security type in the router settings to WPA3, and new ones sometimes conflict with outdated ones WEP or WPA/TKIP. Try changing the security type in the router settings to WPA2-PSK (AES). This is the most universal and stable standard today.
It is also worth checking whether MAC address filtering is enabled on the router. If this feature is enabled and your phone's MAC address is not whitelisted, the connection will be blocked at the IP acquisition stage. Disable MAC address filtering for verification.
What is MAC filtering?
It is a security feature that allows only devices with known physical addresses to access the network. If your phone is not in the list, the router ignores its requests, even if the password is entered correctly.
Using diagnostic commands and ADB
For advanced users with access to USB debugging, it is possible to check the network status through the console. By connecting your phone to a computer with Android Debug Bridgeinstalled, you can run the command adb shell ip addr show. It will show the current state of the network interfaces.
If the interface wlan0 does not have an assigned address or is in the state DOWN, this confirms a software error in the Wi-Fi module driver. In some cases, re-registering the device on the network using the command helps:
adb shell svc wifi disable && adb shell svc wifi enableThis sequence programmatically turns off and on the Wi-Fi module, which is similar to switching the toggle switch in the settings, but is performed at a deeper level of the system. This can help if the interface is stuck in an incorrect state.
⚠️ Attention: Command line interfaces and menu names may differ depending on the Android version and custom firmware. Always check the current commands for your specific device model in the official documentation of the developer.
In 90% of cases, the error “Unable to obtain an IP address” is solved either by rebooting the router or switching to a static IP in the phone settings.
FAQ: Frequently asked questions questions
Why does the error appear on only one device, while others work?
This indicates a local problem with a specific smartphone. Most likely, the network settings on this particular device have gone wrong, or its MAC address has been blacklisted by the router. Try resetting the network settings on the problematic device.
Can an antivirus block receiving an IP address?
Yes, some third-party security applications or firewalls can block DHCP requests, considering them suspicious activity. Try temporarily disabling your antivirus or firewall and check the connection.
What to do if a static IP also does not help?
If manual configuration does not solve the problem, the Wi-Fi module of the phone may be faulty or there is a serious conflict between firmware versions. In this case, it is worth checking for system updates or performing a full reset to factory settings (after making a backup).
Does the date and time affect the connection to Wi-Fi?
Yes, an incorrectly set date and time can cause certification and connection errors, especially in secure networks. Make sure that the “Use network time” option is enabled in your phone settings.