Self assigned IP Address, wireless doesn't work

I have been having the similar issue. I can see Wifi signal, it detects wifi signals, but can not access internet. I removed one of the files refered the other was not found and restarted. I still was not able to access internet and I know it is working with other computer.

I had the "self-assigned IP" problem after installing Leopard on a Powerbook G4 17 inch 1GHz. I went through the "network diagnosis" routine and it had me reboot my cable modem, my wired router, and my AirPort Extreme (old one). Success! Now it gets an IP address. No other issues so far, but I haven't been using it much yet.

Now, why should this be, when it's never happened with any other update? And what is it about rebooting the routers that solves it? No idea.

At least Leopard is nice enough to tell you that it has a self-assigned IP address. In Tiger and earlier, you were just supposed to know that a 169.* address was self-assigned.

Just installed Leopard 10.5 on my PowerBook G4 1.25GHz earlier this week. Just yesterday started getting the same "Self assigned IP" problem that others seem to be getting. It's very annoying. I tried removing the AppleAirPort2.kext extension like is mentioned above but that didn't help things at all.

The way I solved it was by manually inputting my network settings.
So I went to the Network Preference pane and clicked "Advanced...", then under TCP/IP I set "Configure IPv4" to "Manual" and put in my IP address as 192.168.2.20 (an IP I know isn't being used on my home network) and I set my router IP address to 192.168.2.1 (which I know is my router's IP address). The final step to make it work was that I had to click on the DNS tab and manually enter 192.168.2.1 as my DNS server. Once I did that things seem to have worked. Hope that helps someone else out there, and I hope that Apple releases and update to fix this soon.

You got me seemingly 1 step closer, as at least Airport was able to assign an IP address I gave it. But it still will not connect to the internet. I get the same Safari message,

Double check your network prefpane, airport, advanced, proxies.

For some bizarre reason post-10.5 install I had a proxy server configured that I had never entered. Got rid of this and everything was fine.

For troubleshooting, assign a static IP address to the computer in the same subnet as the router (192.168.1.x, 192.168.0.x, or 10.10...). Subnet mask will be 255.255.255.0

Wireless networking will certainly work with a static IP in same subnet. Then, you can troubleshoot cause, monitor user board for solution, or just wait for Apple update. At least the wireless will work correctly in the interim. If you roam with your computer, you can utilize locations where Home uses the static address and other use DHCP.

Hope this helps.

I finally solved the problems in my brothers computer, it was much easier than i though, as simple as this... Open network preferences, then in airport, go to advanced... you will check the box that says disconnect the wireless network when logging out. Ready to go.

I think that what was happening is that the Mac was trying to stay with the ip address, but obviously you must get a new one when you disconnect from the previous one(you lose the connection when you put you mac to sleep). This worked excellent for me.

So I installed Leopard yesterday, and had the same problem. Except that even when I connected to my router with an ethernet cable, I'd still get a self-assigned IP. And everyone else on the network had no problem connecting. I checked out this thread, tried all the proposed solutions, and nothing. Always a self-assigned IP when I connected.

This morning, I decided to bring my computer over to a coffee shop, and BAM! I connect to the wireless here, no problems. Then I try connecting to a friend's wireless router. Again, no problems.

SO, what I'm thinking is Apple made some minor change to the way DHCP works in Leopard, and for whatever reason, certain brands of routers don't know how to interface with it and assign it an IP address.

BTW, the router I have at home is a D-link. I'm not at home right now, and I can't recall the model number off the top of my head, but I'll post it when I get a chance.

Hope this helps at with at least some of you guys out there.

An interesting though. My router at home (where I was having the trouble) is an older Belkin router.

However, I will say that at my university where I work I was having the same problem connecting to the 802.11x network there. I would connect, but just get a self-assigned IP.

i am having the same problems and after reading this still nothing! i have 4 other windows pcs in my house and they work perfectly except one i upgraded to leopard i cannot connect to my home router. i use a linksys WRT300N home router with all the updates and firmware. i used tiger for the 5 weeks ive owned my macbook with no problems at all but once i upgraded to LEOPARD it works about 1 outta 10 times. onc i put it to sleep that when i get the self assigned ip crap. what is the deal with this? i need help!!

I had similar problems and changed my wireless router to use 802.11g only and so far not a problem (nearly 3 days now) on my two macs.

I have a similar experience. My MBP can get wireless at home with no issues. At work, there are two wireless networks, one open, one WEP. I can get into the open network just fine, but I always get the self assigned IP when attempting to get into the WEP network.

I had the same problem many of you had, and solved it after much forum-reading and 3 days of hair-tearing.

Apple has published a page about this fix, sorry, but I don't know the link.

The fix was simple, though I have no clue why it works. They said the problem can be solved by simply restarting in "Safe" mode (hold down "Shift" while restarting). Once in Safe mode you needn't do anything but restart again in regular mode.

Well... I did it and it worked! Has been working fine ever since!

Hope this helps!

Jeff