Diagnose connection issues

A quick-fire guide to network troubleshooting

The first place to check your Mac’s connection is System Preferences’ Network pane. Select Ethernet or Wi-Fi, depending on which one you use. If the circle next to it is red (no connection) or yellow (not configured), the pane should provide info on the problem, such as a missing IP address (the set of four numbers that uniquely identify a device) or lack of an internet connection. If that’s not enough to identify the issue, read on.

1 Check for Wi-Fi problems

Hold å, click the Wi-Fi menu bar icon and choose Open Wireless Diagnostics. Click Continue to let this tool run a series of tests, then click each result for a detailed description of what it has found.

2 Run connectivity tests Use Spotlight ( ç+[ spacebar]) to open Network Utility. In the app’s Ping tab, type your router’s IP address in the box and click Ping. If the packets are all received, the issue isn’t with your Mac.

3 Verify IP settings

Go to System Preferences’ Network pane. Select your connection type and check an IP address has been assigned – if set manually, click Advanced, then TCP/IP; try setting IPv4 to ‘Using DHCP’.

4 Renew the lease

Try renewing the lease of the IP address given by your router. If the issue persists, pick ‘Using DHCP with manual address’; enter an unused one, leave the mask as is, and verify the router address.

5 Forget Wi-Fi network

If you use Wi-Fi, click Advanced, then the Wi-Fi tab, select your misbehaving network in the list and click – (minus) to remove it. Click OK, Apply, then the Wi-Fi menu bar icon and connect from scratch.