How to Fix "Self-Assigned IP" Error on a Mac

Introduction

One possible result of the inability to get online is that you have what is referred to as a self assigned IP address. This usually happens when your router (which normally provides you an IP address) does not provide you an IP address to talk to other computers.

Example of a Self Assigned IP Address

This guide will help you to troubleshoot self assigned IP addresses.

1 Reboot

One of the main causes with the inability to get on the Internet is that your networking equipment could have malfunctioned. Sometimes performing a reboot will resolve this issue.

Your network may consist of one or more of the following networking devices:

Modem

This is the primary device used to get you on the Internet.

  • Has either a coaxial cable, fiber cable, or phone cord plugged into it.
  • Typically has 1 or 2 Ethernet ports which connect to a router.
Gateway

This is an all-in-one device that has both a modem and a router built in. It is a primary device used to get you on the Internet.

  • Has either a coaxial cable, fiber cable, or phone cord plugged into it.
  • Typically has 3 or 4 Ethernet ports which connect to a your computers and smart devices.
  • Typically has Wi-Fi built into it
Router

This device allows you to connect multiple devices to your Internet connection using a single external IP address.

  • Typically has 3 or 4 Ethernet ports which connect to a your computers and smart devices.
  • Typically has Wi-Fi built into it.
Switch

This device helps to extend the wired functionality of devices by providing your additional Ethernet ports.

  • These are typically plug and play.
  • This device is not a router.
Access Point

This device will provide wireless access to your existing network.

  • Used to extend the range of your network
  • Usually plugged into a router / gateway via Ethernet connection.
Range Extender

This device will extend the range of your existing WiFi network by rebroadcasting your WiFi network.

  • Standalone device plugged into a power source.
  • Usually located 15-30 feet from the router.


Next we will want to power cycle the networking devices.

Modem / Gateway

  1. Unplug the power from the device.
  2. Wait 30 seconds.
  3. Plug the power back into the device.
  4. Wait for the device to go online.

Router

  1. Unplug the power from the device.
  2. Wait 30 seconds.
  3. Plug the power back into the device.
  4. Wait for the device to go online.

Switch

  1. Unplug the power from the device.
  2. Wait 30 seconds.
  3. Plug the power back into the device.

Access Point / Range Extender

  1. Unplug the power from the device.
  2. Wait 30 seconds.
  3. Plug the power back into the device.

2 Restart

  1. From the menu bar across the top of the screen, select the Apple menu, then Restart...
    macOS Mojave Apple Menu with Restart highlighted.

? Did this resolve your issue?

  1. Yes
  2. No

We're here to help!

Connect to a Tech Pro

Call or chat with a Tech Pro 24/7.

One possible result of the inability to get online is that you have what is referred to as a self assigned IP address. This usually happens when your router (which normally provides you an IP address) does not provide you an IP address to talk to other computers.

Example of a Self Assigned IP Address

This guide will help you to troubleshoot self assigned IP addresses.

One of the main causes with the inability to get on the Internet is that your networking equipment could have malfunctioned. Sometimes performing a reboot will resolve this issue.

Your network may consist of one or more of the following networking devices:

Modem

This is the primary device used to get you on the Internet.

  • Has either a coaxial cable, fiber cable, or phone cord plugged into it.
  • Typically has 1 or 2 Ethernet ports which connect to a router.
Gateway

This is an all-in-one device that has both a modem and a router built in. It is a primary device used to get you on the Internet.

  • Has either a coaxial cable, fiber cable, or phone cord plugged into it.
  • Typically has 3 or 4 Ethernet ports which connect to a your computers and smart devices.
  • Typically has Wi-Fi built into it
Router

This device allows you to connect multiple devices to your Internet connection using a single external IP address.

  • Typically has 3 or 4 Ethernet ports which connect to a your computers and smart devices.
  • Typically has Wi-Fi built into it.
Switch

This device helps to extend the wired functionality of devices by providing your additional Ethernet ports.

  • These are typically plug and play.
  • This device is not a router.
Access Point

This device will provide wireless access to your existing network.

  • Used to extend the range of your network
  • Usually plugged into a router / gateway via Ethernet connection.
Range Extender

This device will extend the range of your existing WiFi network by rebroadcasting your WiFi network.

  • Standalone device plugged into a power source.
  • Usually located 15-30 feet from the router.


Next we will want to power cycle the networking devices.

Modem / Gateway

  1. Unplug the power from the device.
  2. Wait 30 seconds.
  3. Plug the power back into the device.
  4. Wait for the device to go online.

Router

  1. Unplug the power from the device.
  2. Wait 30 seconds.
  3. Plug the power back into the device.
  4. Wait for the device to go online.

Switch

  1. Unplug the power from the device.
  2. Wait 30 seconds.
  3. Plug the power back into the device.

Access Point / Range Extender

  1. Unplug the power from the device.
  2. Wait 30 seconds.
  3. Plug the power back into the device.
  1. From the menu bar across the top of the screen, select the Apple menu, then Restart...
    macOS Mojave Apple Menu with Restart highlighted.

Next we need to know how your device connects to the Internet.

  • Wireless - You connect using a wireless router or access point.
  • Wired - You use an Ethernet cable plugged into your gateway, router, or switch and the other end is plugged into your device.
  1. Click the Apple Menu and then click on System Preferences.
    Apple Menu with System Preferences highlighted.
  2. Click on Network.
    Network icon highlighted
  3. Click the connection you are having a problem with on the left.
    Connections highlighted
  4. Make sure Configure IPV4 is Using DHCP.
    Using DHCP is highlighted
  5. Click on Advanced.
    Advanced button is highlighted
  6. Click Renew DHCP lease.Renew DHCP Lease highlighted
  1. Click the Wi-Fi icon in the menu bar. By default it will be in the upper right corner near the time and date.
    Wi-Fi symbols.
  2. If Wi-Fi is off, choose Turn Wi-Fi on.
    macOS Wi-Fi menu with Wi-Fi On highlighted.
  3. Select Open Network Preferences.
    Wi-Fi menu with Open Network Preferences highlighted.
  4. Select Advanced within the Network window.
    Network Preferences with Advanced highlighted.
  5. In the Preferred Networks list, select the network you wish to forget. Tap the minus icon (-) to forget the network.
    Advanced Network Preferences Wi-Fi tab with Network list, add, and remove highlighted.
  6. Your device will no longer join this Wi-Fi network unless you reconnect once again.
  1. Click the Wi-Fi icon in the menu bar. By default, it will be in the upper right corner near the time and date.
    Wi-Fi symbols.
  2. If Wi-Fi is off, choose Turn Wi-Fi on.
    macOS Wi-Fi menu with Wi-Fi On highlighted.
  3. The strength of each nearby network is shown next to its name. More darkened bars indicate a stronger network connection.
    Wi-Fi menu with signal strength indicator highlighted.

  4. Select the Wireless Network Name (SSID) of the network you want to connect to.
    Wi-Fi menu with networks highlighted.
  5. Networks that have a lock icon next to their name require a password. After you select your network, enter the network password when you're prompted. If you don't know the network password, check with the owner of the Wi-Fi network you're trying to join.
  1. Open the Finder from the dock.
    Finder highlighted
  2. Click on the Go menu.
    Go menu highlighted
  3. Click on Go To Folder...
    Go To Folder highlighted
  4. Type "/Library/Preferences" in the box.
    Go to folder text box highlighted
  5. Click the Go button.
    Go button highlighted
  6. Find the file named "com.apple.alf.plist" and drag it to the trash.
    plist file being dragged to trash can
  1. From the menu bar across the top of the screen, select the Apple menu, then Restart...
    macOS Mojave Apple Menu with Restart highlighted.
To help troubleshoot the problem we should check if other devices can connect to the wireless network.
  1. Click the Apple Menu and then click on System Preferences.
    Apple Menu with System Preferences highlighted.
  2. Click on Network.
    Network icon highlighted
  3. Click the connection you are having a problem with on the left.
    Connections highlighted
  4. Make sure Configure IPV4 is Using DHCP.
    Using DHCP is highlighted
  5. Click on Advanced.
    Advanced button is highlighted
  6. Click Renew DHCP lease.Renew DHCP Lease highlighted

While Ethernet connections are typically the most reliable connection to the Internet, there are still some issues that can arise. Test your connection after each of these steps.

  • Plug your Ethernet cable into another port on your Gateway, Router, or Switch.
    Animated GIF indicating to plug your cable into another port
  • Try using another Ethernet cable.
  • If you are plugged into a switch, try plugging directly into your Gateway or Router.
  1. Open the Finder from the dock.
    Finder highlighted
  2. Click on the Go menu.
    Go menu highlighted
  3. Click on Go To Folder...
    Go To Folder highlighted
  4. Type "/Library/Preferences" in the box.
    Go to folder text box highlighted
  5. Click the Go button.
    Go button highlighted
  6. Find the file named "com.apple.alf.plist" and drag it to the trash.
    plist file being dragged to trash can
  1. From the menu bar across the top of the screen, select the Apple menu, then Restart...
    macOS Mojave Apple Menu with Restart highlighted.
To help troubleshoot the problem we should check if other devices can connect to the wireless network.
We use cookies on our website to enhance your experience, analyze site usage and support our marketing efforts. To learn more, visit our Privacy Policy. By clicking “Accept”, you agree to our use of cookies and similar technologies.
Accept