Mac OS X Lion/Mountain Lion - Could not join network/timeout

I was migrating all the data from a friend's old MacBook (which was running Mac OS X Tiger) to her new MacBook Air (running Mac OS X Mountain Lion), and besides a WiFi hiccup, everything went smoothly (I had to clone the old MacBook's drive to a USB disk, then use Setup Assistant to migrate the data from that disk to the new MacBook Air).

During the Setup Assistant, I could easily connect to my WiFi network, but after the migration was complete, I couldn't connect anymore. I kept getting a pesky error: "Could not join [network]. A connection timeout has occurred." (see picture of error dialog here). Looking through Apple's forums and elsewhere was not much help, because this message seems to be a very generic 'something weird happened' error, happening in many different circumstances.

However, knowing that the keychain and old WiFi connection data from the old Mac had transferred over to the new Mac, and knowing that something might've gone screwy with the network information, I decided to do the following:

  1. Open Keychain Access and delete the password for my WiFi network from the Keychain.
  2. Open System Preferences, and click on Network. Then select 'Join Other Network...', but type in the name of my own network, but with an incorrect password. Click connect, and the connection will fail... but next time, it won't!

I think Apple may have some bug that causes Keychain items and WiFi network data to get corrupt or outdated, and that's what probably caused the problem in my case. Now I can successfully log into my WiFi network on the new MacBook Air!

Further reading

wifi
airport
macbook air
migration assistant
setup assistant
mac
lion
mountain lion

Comments

Thanks for this one. Bugs keep on coming with Apple...quality is dropping...

Solution: Launch the "KeyChain Access" application. Select "Passwords" on the left navigation area under "Category". Then in the search box on the top right, enter the SSID of your wireless network. In my case, I typed "wide". You will see two or four entries where the name is your SSID. Delete all the entries. The next time you connect, it will re-create the necessary records. This might solve your issue.

Workedddd!!!!!! Had been struggling for months. Nothing else worked. This did! Thanks a ton, bro!

i just did migration assistant and on new macbook air, it's connection to my wifi network, but safari can't load an internet page. it just says I'm not connected to the internet. what can i do?