wi fi not working

Hi trailer15,

Welcome to the Support Communities!

The article below may be able to help you with this issue.

Click on the link below to see more details and screenshots.

I've quoted some helpful highlights for you:

Wi-Fi: How to troubleshoot Wi-Fi connectivity

http://support.apple.com/kb/HT4628

OS X v10.7 Lion and Mac OS X v10.6

Note: The screenshots and specific menu choices in this article apply to OS X Lion v10.7 and later. The concepts are the same for Mac OS X v10.6 Snow Leopard, except AirPort appears instead of Wi-Fi in places such as the Network pane of System Preferences.

Preparation

First, determine what the issue is. Knowing what's wrong will help you identify appropriate troubleshooting steps.

1. Does the symptom occur with more than one Wi-Fi device?
   
   • Wi-Fi issues may be related to the network in question or they may be related to the Wi-Fi computer joining that network. Usually, if other computers or devices (such as the Apple TV or iPhone) are able to get on the Internet without issues, then your Wi-Fi router is probably fine.
   • If you only have one Wi-Fi device, proceed with this article.
2. Make sure your software is up-to-date.
   
   • Install all software updates available for your Mac.
   • If you use a third-party Wi-Fi router, check with the manufacturer to confirm that it has the latest firmware installed. If an update is available, follow the manufacturer's instructions for updating the firmware.
   • To determine if your Apple Wi-Fi base station firmware is up-to-date, see Updating your software.
3. Check your connections.
   

   Some networking issues may be caused by loose or disconnected cables. Verify that all Ethernet and power cables connected between your modem and your Wi-Fi router are correct. Checking that devices such as your router and modem are on, disconnecting and carefully reconnecting Ethernet cables, and/or replacing damaged Ethernet cables may resolve the issue without any further troubleshooting.

4. Verify that you are using the recommended settings for your device.

   See Recommended settings for Wi-Fi routers and access points.

5. Restart your network devices.

   Powering your modem or router off for a few seconds and then on again may resolve network issues without any additional troubleshooting. If you have phone service through your ISP, power cycling your modem may interrupt that service. You may need to contact your ISP in order to restore your phone service if your modem is reset or powered off. Ensure that you have alternative means to contact your ISP (such as a cell phone) to avoid unnecessary delays in restoring your Internet or phone service.

Troubleshooting Click the solution link that appears below the Wi-Fi symptom.

Symptom: My Mac does not connect to the Internet

• Webpages do not open in Safari or other web browsers. These pages may be blank or you may receive an alert that "You are not connected to the Internet".
• Internet applications such as Mail, iChat, or the App Store cannot connect to their servers.

Note: Routers may be configured to allow some services to use the Internet (such as Mail) while preventing other services from using the Internet (such as web browsers). If you are not sure whether your network is configured in this manner or not, contact your network administrator. If your network is not configured in this manner and some Internet applications work, but others do not, then the issue is probably not related to your Wi-Fi network.

I hope this information helps ....

Have a great day!

- Judy