MacBook Pro will not connect to Cisco Wireless Network

Question

I have just bought a brand new MacBook Pro, running Leopard (OSX 10.5.1) and I just cannot get it to connect to the Wireless Network at my workplace.
The MBP connects to wireless network and authenticates just fine, but will not obtain an IP address from the DHCP server.
The wireless network consists of 16 Cisco Aironet 1200 Access Points controlled by a Cisco Wireless Network Controller. It does not broadcast its SSID and is WEP 128-bit hex protected.
Changing the network from WEP to WPA is out of the question for me as this is under the control of my customers IT Department and they do not have any problems with their PCs connecting to the network. It appears to be an Apple issue.
For reference, my old Vaio PC, my Nokia N95 and my iPod Touch ALL connect to the same wireless network without any problems whatsoever, first time, every time!
If I boot into Windows XP from my Boot Camp partition, XP can connect wirelessly to the network without any problems, so it is not MacBook hardware related...
It has to be a bug in Mac OSX... doesn't it?!?
Things I have already tried (following suggestions on many forums):
* Switching Airport off/on
* Deleting various network-related Plist files and rebooting
* Manually assigning an IP Address (not really permitted but doesn't work anyway!)
* Disabling all network adaptors except Airport
AP Grapher shows that the MBP is connected to the wireless network, at good strength, and packets are being sent and received, but Internet Access is not possible as no IP Address has been assigned. Instead, my MBP shows a 169.* IP Address (self-assigned). It should be a 10.1.255.* address.
Can anybody please help? Thank you.

Answer 1

i posted this same reply elsewhere because it worked for me for my Buffalo wireless router: try manually setting your IP address instead of relying on DHCP, which sometimes (I don't know why) doesn't work well with Macs. It's a good get around. I am a happy Mac user but nothing is perfect on earth, and when the Mac gives problems, it does give a lot of frustration. Macs are not as easy to troubleshoot as Win because a Mac is built to be user friendly(and it works most of the time), meaning a lot of the background computing stuff is hidden away from users to avoid user accidentally upsetting some settings.
Unfortunately, the highly automated troubleshooting wizards provided by OS X are not perfect so when these software wizards fail to resolve the problem, like my Network Diagnostics, I have to spend more time tinkering around. There's "Terminal" of course but then most of us, especially PC converts to Macs, don't know how to use it.
You should also try updating your MBP, see if there are any new updates being released.