Member Avatar for ilyons

Hey guys,

I'm hoping this is a well-known problem with a simple fix: I work at a study abroad program and most of the web-related problems that I see involve Vista machines that aren't picking up settings via DHCP. Windows 7, XP, OS X -- all fine. They'll auto-assign a bizarre IP like , as computers are wont to do when they don't pick up settings. I've tried turning off IPv6 support and have experimented with turning the broadcast flag off -- to no avail, obviously, since I'm writing here.

My solution so far has been to assign the users a static IP (under the alternate configuration setting) outside of the DHCP range, which works beautifully, but I'd like it to work appropriately.

The setup (in this case) is a Linksys/Cisco WAP4410N AP that gets its DHCP information from a Linksys RV082 router that is acting as the gateway.

Any ideas? Is it Vista-related, or am I doing something incorrectly?

Thanks in advance for the help.

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  • Latest Post Latest Post by mr_mark_king

Dani AI

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Vista clients failing to get DHCP leases while other OSes work most often means DHCP packets are being blocked or dropped somewhere in the DHCP handshake (client, AP/router, or a middle utility), rather than a fundamental IP-stack failure. The working manual address reported in the thread points the diagnosis toward the DHCP negotiation path. The most efficient approach is a short, ordered checklist that isolates client vs. infrastructure problems and then looks at the usual Vista-specific culprits (drivers, third‑party networking software, power settings, and service/stack corruption).

  1. Quick split test (as suggested by @mr_mark_king): connect the same Vista laptop wired to the router. If DHCP works wired but not wireless, concentrate on AP/router mode, firmware and wireless drivers. If DHCP fails wired too, concentrate on the client.
  2. Capture basic status: run ipconfig /all and save the output for troubleshooting. Look for "DHCP Enabled", "DHCP Server" and lease timestamps.
  3. Reset the client network stack (elevated prompt): 
ipconfig /release
ipconfig /renew
ipconfig /flushdns
netsh int ip reset C:\resetlog.txt
netsh winsock reset

Reboot after these commands.
4) Restart and confirm Windows services: ensure DHCP Client, Network Location Awareness and WLAN AutoConfig are running and set to Automatic.
5) Check antivirus/firewall and vendor wireless utilities: temporarily disable/uninstall third‑party firewalls (Symantec, ZoneAlarm, etc.) and any vendor wireless manager so Windows manages the adapter.
6) Update drivers and firmware, and check adapter power options (Device Manager -> Power Management -> uncheck power‑save). Try forcing b/g mode if N mixed mode looks flaky.
7) AP/router checks: verify the AP is in plain AP/bridge mode (not router/guest mode), disable client isolation, check DHCP scope size, and update firmware.
8) If needed, capture DHCP traffic with a packet capture (filter "bootp") from both a wired client and AP side to see whether DISCOVER/OFFER packets are leaving/arriving — that directly shows whether the problem is client or infra.

If a quick fix is required, DHCP reservations keyed to the client MAC on the router are less error‑prone than per‑machine static settings. The above routine isolates the likely cause and avoids guessing; it also addresses the common Vista-specific interference points that often show up in mixed OS environments.

Recommended Answers

All 10 Replies

Member Avatar for Maplestory

I Got An Idea. Either You Did Not Connect The Modem To Your Internet On You Router...

But If This Presist , Go To Your Back Of Your Router And Pock A Small Pen On The Reset Button...

Member Avatar for mr_mark_king

on the Linksys/Cisco WAP4410N AP is there an option to enable DHCP Relay?

Member Avatar for ilyons

Good idea, but I don't see one -- I also think it strange that it's only Vista machines that have this trouble; every other OS functions perfectly. There are other Access Point modes, but most seem to be targeted towards turning the device into a wireless repeater.

Member Avatar for mr_mark_king

ok doesn't look like it will be down to relaying then. what happens if you plug the Vista computer directly into the router? Can it get an IP then?

Member Avatar for mr_mark_king

here is a potential solution:

Member Avatar for ilyons

Like I said in my original post, I've experimented with turning the broadcast flag off, but it didn't seem to help at all.

Member Avatar for mr_mark_king

are you running any symantec software?

Member Avatar for ilyons

Good question. The PiQs (PCs in Question) are the students' machines that they bring from their apartments and use to connect to the wireless here. I hadn't been looking for that as a problem, but it's very possible.

I'll try to appropriate one and plug it directly into first the gateway to see if it will assign an appropriate IP that way and, if it does, will then plug it into the access point.

I appreciate the help, mr_mark_king.

Member Avatar for ilyons

Hm. Someone with Vista just came up to my desk and had no problems connecting beyond the fact that he couldn't figure out how to get past the PIN code request... did not have Symantec. You could have something...

Member Avatar for mr_mark_king

fingers crossed :-)

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