Wrong IP from DHCP whe using Wi-Fi

[Davesdream]

Hello,
Why I keep getting a wrong IP address(from different network) when set to DHCP? I get an IP and subnet mask, but an empty Router
If I change to manually IP to make sure I give it an IP address that's inside my network, It can't even connect to the Access Point/Router...

[aneagle]

What is the wrong IP looks like? The usual scenario is the router has a too small DHCP serving range and the setting is somehow doesn't release the unused IP from the DHCP table, the router DHCP server is too busy to respond to the IP request and the client(in this case the iPhone) has to self assign a limited connection IP. You may access the router from a PC and check the LAN status/DHCP table when this occurs to have a clear idea where the problem is. The quick fix is to restart the router (power off then on).

[Davesdream]

When I said "wrong IP" is the default 168.* and a 255.255.0.0 subnet and EMPTY router. The router is the typical Linksys wireless router. Only 2 devices are connected at home (desktop & laptop) DHCP starts to assing IP's from *.*.*.100, When I test I'm only 4-5 feet away from it. It recognize the network (wich is not broadcasting the SSID and WEP security), and shows the name and check mark, so that is telling my is connected to this specific network.
I tried turn on and off the router too.
An Update. This morning I was driving by Downtown. In a traffic light I check the phone and it was picking the open Wireless Downtown signal and I was be able to connect and use Safari.
For some reason, if I cannot connect at home and at the office, where both networks have password, seems like the IPhone doesn't like that, but it can connect when the Wi-Fi is open.
Any idea why then???

[aneagle]

This may also happen after restoring to a new version and using the old backup from iTunes. You can try Settings/General/Reset/Reset Network Settings, restart and enter SSID, select WEP security and enter the WEP key.

[Davesdream]

Tried that already...

Ok guys. I want to let you know I fix the problem. For some reason IPhone doesn't like WEP key (at least on Linksys WRT54GS... or just mine). But it work this way though. First I disable password (without broadcasting the SSID) and no problem to access internet. Then I tried using WPA2 Personal in password and this way it works.
Anyone had this problem with Linksys/wireless/WEP ??
Well, for me it works now...

[aneagle]

I think it's the Linksys, it recognizes the WEP key in Hex format but not the ASCII pass phrase. I don't know why but I got this problem on every PC in my office.

[Davesdream]

It seems is a problem with Linksys wireless router and WEP Key.
At least this is what one of the "more..." pages in the router says:
"WEP:
Default Transmit Key: The key you would like to use for transmitting WEP keys.
WEP Key Bit: You may select from 64-Bit or 128-Bit encryption.
Passphrase: You may enter a passphrase consisting of any keyboard character to be used to generate a hex WEP key. Passphrase option is only supported when you are only using Linksys devices on your network."
Well, this is some kind wrong. I've been using the Hex WEP Key with the laptop and had no problem to connect (and it wasn't Linksys Wi-Fi) component, but the Iphone didn't work.
On the other hand seems to be true, when I switched to another security method. All the devices worked.