No DHCP
 

Hi,

Intresting one this...

Just got a new router - ZyXel P-660HW-T1.

Installed and working - DHCP server enabled with a pool of 50 IP addresses.

One PC connected gets an IP, along with wireless clients.

However, my PC won't obtain an IP address.

(My PC goes through a 1Gb switch).

So far, I've rulled out Kaspersky IS, Windows Firewall, and the switch / cabling - i.e. - connected the PC direct and tried all the ports on the router.

If I put a static IP, subnet, default gateway and DNS I get net access, can access web and the web interface of the router.

Can't see anything in the logs...

Any ideas??

Re: No DHCP
 

I'd try uninstalling the network drivers, reboot and reinstall.

Re: No DHCP
 

Done - uninstalled device from DM, keeping drivers...reinstalled - all installed ok but same issues...

Re: No DHCP
 

If you reboot everything and leave the laptop out of the equation, can your PC connect?

Re: No DHCP
 

No need to reboot - another PC connected wired works perfectly fine in all 4 ports.

Will try Safe Mode with Networking on the PC with issues next...odd that it works with a static and not DHCP!

Re: No DHCP
 

The reason I asked was that I was wondering if it was working as a wireless access point rather than a router. I don't know this particular router you've got so can't tell you where to look to see if a radio button or check box is wrongly selected but that is a symptom of a router acting as a wireless access point. I made that suggestion because if after rebooting you can connect wirelessly with your PC this could discount or perhaps confim that/

Re: No DHCP
 

It's a router - status says router!


As I say - works ok from all other PC's / laptops - just the one PC playing up...

Re: No DHCP
 

Sorry misreading you. So it is connecting wirelessly to more than one device at the same time.? I thought the second device could only connect when wired.

Can you swap wireless cards/dongles round or is that too much hassle?

Re: No DHCP
 

Have two laptop - both work wireless on DHCP

1 Desktop PC - works on DHCP

1 Desktop PC - will not obtain IP via DHCP - put a static IP and it works fine.

Re: No DHCP
 

do you get an IP if you bypass the switch?

Re: No DHCP
 

A strange one, Is it just picking up a 169.X.X.X address when you do an ipconfig/all ?

Re: No DHCP
 

Nope - already ruled that one out by direct standard patch cable.

Bit of a head scratcher uh??!!

Re: No DHCP
 

Have you tried any of the other laptops/pcs wired through the switch?

Re: No DHCP
 

what message are you getting in the system event log? (not the router log, but the computer log)

---------- Post added at 20:39 ---------- Previous post was at 20:37 ----------

i don't suppose the router is only set to dish out DHCP to wireless clients, is it? I doubt the zyxels have the option to split, but take a look...

Re: No DHCP
 

The 169.x.x.x is an APIPA(automatic private ip addressing) IP address, your computer assigns itself one of these addresses when it can't find a DHCP server.

Did you say you were going to try safe mode with networking? What were the results of this?

On the PC that won't get an IP address, have you ever had Zonealarm or any other firewall software installed on it?

BTW, the way I under stand this is that Lee has got: 2 x wired pc's, both on DHCP, only one working and 2 x laptops on wireless set to DHCP that are working.

Re: No DHCP
 

zonealarm can mess things up if you 'improperly' remove software it's keeping an eye on. this can cause issues. second to that, if the zyxel is running a non-MS DHCP service, the DHCP discover message from the client can sometimes get confused by the DHCP service, meaning that the router can't give out the address correctly as it routes the return message to the wrong place.

try the following commands....


ipconfig /flushdns
ipconfig /registerdns
ipconfig /release
ipconfig /renew

---------- Post added at 20:48 ---------- Previous post was at 20:46 ----------

does sound likely to be a firewall thing though. try turning them all off and try again

Re: No DHCP
 

Nope - the other working PC is directly connected and I've directly connected the non working PC direct to the router with the same issue.

---------- Post added at 20:52 ---------- Previous post was at 20:50 ----------

DHCP message - without looking it's from DHCP Client saysing it could not obtain an IP address...

The other PC is working so I know the DHCP server is working correctly.

---------- Post added at 20:53 ---------- Previous post was at 20:52 ----------


Good shout on the commands - I've tried the ipconfig / renew etc but not the flush and register...

Firewall - the PC is running KIS2009 - and so is the working PC...

Re: No DHCP
 

That's just give me a thought.

Lee, the PC that's not working, it is using it's factory set default MAC address isn't it. You've not spoofed it at any point and duplicated it at all by any chance?

---------- Post added at 20:55 ---------- Previous post was at 20:54 ----------

Either turn it off.....and make sure it's off, or boot into safe mode with networking.

Re: No DHCP
 

Have you a spare NIC you could swap into the problem PC?

Re: No DHCP
 

i had a problem where DHCP kept dropping on my pc. Turned out to be Internet security messing with connection.

Re: No DHCP
 

Plot thickens....

Other wired PC's through the switch work correctly - they pickup a new correct IP.

It's something to do with my Vista install...

I've tried reseting the router - back to defaults - picked up an IP on the problem PC...cool...so went and changed the router IP from 192.168.1.1 to 192.168.10.1 and setup the DHCP server accordingly - start at 192.168.10.100 - pool of 100 addresses.

Rebooted problem PC - no IP again - switched on another wired PC - got an instant 192.168.10.100 IP address....

WTF is up with my Vista??!!

Could it be the original router I had was also set to 192.168.10.1 and Vista has remembered some settings for this?

Ran a Route Print but did not see the routes in the table....

What is going on!!!!

Re: No DHCP
 

http://support.microsoft.com/kb/928233

maybe..

Re: No DHCP
 

default gateway 192.168.1.1
from : http://www.dslreports.com/forum/r191...ction-problems

Re: No DHCP
 

Lee, you need to either try safe mode or another NIC.

also try DaiNasty's MS link, sounds relevent

Re: No DHCP
 

have you flushed and re-registered your DNS from the client yet?

Re: No DHCP
 

:D:D:D:D:D:D:D:D:D:D

Yay!!!!!! Fixed! Bloody Vista!!!

It needed that reg Dword added - DhcpConnEnableBcastFlagToggle and a reboot...

Thank's for the help all - for a moment I thought I had a duff On-Board LAN NIC...

Re: No DHCP
 

I'd wondered about the NIC as well but thought the reg hack was worth a try. Glad to hear it worked, I love a happy ending.

:)

Re: No DHCP
 

Well as I said - it worked fine with a static, so the hardware was ok - didn't work in Safe Mode /w Networking so we could rule out the firewall software - didn't work directly connected to the switch either so that ruled out the switch - it could have only been one thing....Vista's config.

Don't you just love troubleshooting!!! :rolleyes:

Actually - looking back at my work mail one of my colleagues had the same issues a few weeks ago and fixed it using the same reg key!

Re: No DHCP
 

And just as we're getting our heads around Vista, here comes Windows 7 with a whole new batch of headscratching built in..

;)