Hi all,
I have a problem with connecting a laptop to a LAN. The problem is, as I think, that the computer is unable to obtain an IP adress from the DHCP server. As ipconfig shows, the machine even does not know the IP adress of the DHCP server. Does anybody have an idea how to tell the laptop at which IP adress it should look for the DHCP server (ipconfig writes DHCP's IP 255.255.255.255)?
Thanks for any idea.

You have it backwards, Lukas. The laptop doesn't need to know (nor can it know) the IP address of a DHCP server before it leases an address.

How is the laptop connecting to the network? wired or wireless? Can the laptop lease an address on any other network?

your wrong jimminy, you can tell what computer in what DHCP server you want them to use, it's called C:>ipconfig /showclassid , switch long story.. if your getting a 169.254.X.X address, it's not seeing the DHCP server. I would do a c:>ipconfig /all and post the results here.

If the laptop is not getting an ip address, it can be few things:

1 - the connection to the dhcp server is broken (bad cable, bad ethernet card, etc...)

2 - the dhcp server might have run out of ip addresses

3 - dhcp server might have assigned ip address already, but the laptop didn't pick it up (I am fighting this last one myself now)

Brian, the DHCP class ID client setting functions by specifying a desired DHCP server's class ID, not its IP address. It is technically correct to say that you cannot specify a DHCP server by IP address. You can read more about BOOTP and DHCP here if you're interested.

That being said - I wonder if setting the class ID is a requirement on the network Lukas is connecting to. Or rather, is not connecting to :)
Your suggestion to post output of ipconfig is a good one. We need more information to determine what's really going on.

Back to the original question, go into your network settings on the laptop and check the properties for TCP/IP. Should be set to "Get IP Address Automatically" and "Use DHCP Server for WINS Resolution". You've indicated it's running Win98 so you don't have the XP firewall problem, but do you have another firewall running on the laptop? If so go into its setup and configure it to treat IP range 192.168.0.1 through 192.168.255.255 as "local" or "trusted".

Go to the command prompt and enter

PING 127.0.0.1

to make sure your adapter is connected properly and the drivers are installed. If you get an OK back it should be good to go, otherwise reload the drivers and make sure it's seated securely.

I got the same problem with Lucas. My OS is XP. I've tried to ping 127.0.0.1: It's ok
I've tried c:>ipconfig/all. I got:

Window IP config:
Hostname: VALUE-ECECF7F4
Primary Dns:
Mode Type: Hybrid
IP Routing Enable: No
WINS Proxy Enable: No

Ethernet adapter Local Area Connection:
Physical Address : 00-0-6E-93-A6-BC
Dhcp Enabled : Yes
Auto config Enable : Yes
Auto config IP address: 169.254.46.239
Subnet Mask : 255.255.0.0
Default Gateway :

Thks in advance for any suggestions, inputs

Addition info on Ethernet adapter

The Connection-specific DNS Suffix: is blank instead of cable company internet link.

Guys,

Is this a bug in the latest MS security update?

I've had similar 'not getting DHCP response' things on two PCs now.

if running ipconfig tells you your computer has an IP address of 169.254.xx.xxx, this is Microsoft's way of telling you ''we couldn't obtain an IP address, so here's this bogus one." Any IP address like 169.254.xx.xxx is not a real IP address. You'll need to do an ipconfig /release to get rid of the bogus ip address, then an ipconfig /renew to get a good one. (possibly something like 192.168.x.x) but definitely not 169.254.x.x. You may have to type ipconfig /renewall or ipconfig /releaseall, this changes from system to system. lemme know if you need any more help, i'm glad to provide it. i just took network communications in college last term and learned all about this kind of stuff =)

Andy
andycool22@peoplepc.com

You need to keep studying, methinks ;)

>>Any IP address like 169.254.xx.xxx is not a real IP address

This is wrong. IP addresses in the range 169.254.0.0 -169.254.255.255 are perfectly valid. They are reserved by IANA for automatic private IP addressing, which is what happens when Windows cannot contact a DHCP server.

>>this is Microsoft's way of telling you...so here's this bogus one

This is a platform-independent addressing behavior, not Microsoft's. See above.