Black Macbook connection problem

Question

Hello
We have 4 Apple computers in our household. We're connecting to the internet using an airport express. Three out of four computers (G4 Titanium Powerbook, late 2008 MacBook Pro, late 2008 Alu Macbook) can connect to this AE very quickly and the speed is fine. One computer (black Macbook 2.16 Core2Duo) has problems. When starting up or waking up from sleep it takes about a minute to find the AE, and then when finally connected it's very slow. I tried to set up the AE from this computer and interstingly, then all other computers can not find the network at all.
Anyone any ideas ?

Answer 1

I had a very similar problem with a PowerBook G4 that I inherited. The final resolution was to do a complete flatten and reload of OS X, but there are a few steps you can try first that are a bit less drastic:
Try the following, and check to see if the problem disappears after each step ...
1a. Delete Preferred Network(s)
o System Preferences > Network > AirPort > Advanced > AirPort tab
o Under "Preferred Networks," delete the network(s) you regularly use from the list.
1b. Delete AirPort Keychain Entries
o Launch the "Keychain Access" application located in Applications/Utilties.
o Click on the "Kind" filter at the top, and look for any "AirPort network password" entries...and delete them.
o Restart, or log out then back in.
1c. Add Preferred Network(s)
o System Preferences > Network > AirPort > Advanced > AirPort tab
o Add the preferred network(s) using the "+" button.
o Restart or log out then back in.
2. Run the Disk Utility to repair Disk Permissions.
3. Turn off the Mac OS X Firewall
o System Preferences > Sharing > Firewall
o Click the "Stop" button.
4. Move System Configuration Files
(Note: You will have to reestablish your network connections settings.)
o Go to /Library/Preferences
o Move the SystemConfiguration folder and com.apple.networkConfig.plist file to the desktop.
o Restart your Mac. (Note: OS X will rebuild the files that are now sitting on your desktop. If this doesn't resolve the issue, you can move the folder & .plist file back to it's original location.)
5. Create a New User Account
o System Preferences > Accounts
o Click "+" to add a new account
o Log off, then log back on with the new user account.
o Try connecting with the AirPort.