[Okta Webinar] Learn how to a build a cloud-first strategyRegister Now


I have computers on my LAN that keep getting IP conflict errrors

Posted on 2011-11-01
Medium Priority
Last Modified: 2012-05-12
I have users reporting that they are recieving IP confilict errors on their computers.  How do I identify what computer is causing the conflict?  I am running Windows Server 2008 and the client is XP Pro.
Question by:submarinerssbn731

Accepted Solution

kcoect earned 668 total points
ID: 37062677
If you go to a machine that doesn't have an IP address conflict, you can bring up a command prompt and do the following

nbtstat -A <ip in conflict>

That will reply with NetBIOS name associated with that IP address (if the machine doesn't have it's firewall up)...

Alternativly, you can look in DHCP and see what machine has been given that IP address by the DHCP server...

Assisted Solution

cbocan earned 668 total points
ID: 37062689
Try to remote connect to that IP then setup a (temporary) fix IP for it.
You can run arp -a on a command prompt then see the MAC address. This might help

Assisted Solution

Americare earned 664 total points
ID: 37063081
Click Start > All Programs > Administrative Tools > DHCP

Your server should be listed there (assuming it's the DHCP server, and it should be)

Expand your server name, > IPv4 > Scope > (double click Address Leases)

Should show you all the reservations created on your network.  Get the IP addresses from the machines that are causing the issues, ensure that they don't have a static IP set (if you need help with this, ask and I can give you directions).

You can then do one of two things.

You can assign the ip addresses manually on the XP machine (which is my least favorite of the two options)

Or you can set a address reservation in the "Reservations" pane under "Scope"

I would create a reservation for the two machines that are conflicting.  Assigning them both different IP addresses.

I would also open command prompt on the xp machines and run the following after making the reservations in scope:
"ipconfig /flushdns"
"ipconfig /release"
"ipconfig /renew"

That should eliminate your problems.


Author Comment

ID: 37070214
This is what I got when I ran the nbtstat.  Why does the DELLPURCHLG show up twice?

C:\Program Files\Support Tools>nbtstat -A

Local Area Connection:
Node IpAddress: [] Scope Id: []

           NetBIOS Remote Machine Name Table

       Name               Type         Status
    DELLPURCHLG    <00>  UNIQUE      Registered
    DELLPURCHLG    <20>  UNIQUE      Registered
    PLASTICSOLUTION<00>  GROUP       Registered
    PLASTICSOLUTION<1E>  GROUP       Registered

    MAC Address = BC-30-5B-D8-8D-3F

C:\Program Files\Support Tools>

Author Closing Comment

ID: 37075637
Good answers thanks,

Featured Post

Creating Active Directory Users from a Text File

If your organization has a need to mass-create AD user accounts, watch this video to see how its done without the need for scripting or other unnecessary complexities.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Sometimes drives fill up and we don't know why.  If you don't understand the best way to use the tools available, you may end up being stumped as to why your drive says it's not full when you have no space left!  Here's how you can find out...
In this article, we’ll look at how to deploy ProxySQL.
This tutorial will walk an individual through the steps necessary to enable the VMware\Hyper-V licensed feature of Backup Exec 2012. In addition, how to add a VMware server and configure a backup job. The first step is to acquire the necessary licen…
Here's a very brief overview of the methods PRTG Network Monitor (https://www.paessler.com/prtg) offers for monitoring bandwidth, to help you decide which methods you´d like to investigate in more detail.  The methods are covered in more detail in o…
Suggested Courses
Course of the Month19 days, 13 hours left to enroll

872 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question