IP conflict on domain controller

For a while now, i've been getting IP error conflicts on one of my DCs. Obviously the DCs have static IP addresses and the MAC address in the error is assigned through DHCP. Ip of the DC is 0.100 and the ip of offender is 10.20.
Is is possible that the TCP/IP stack is corrupted or Bad nic?

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MAC addresses aren;t assigned thorough DHCP so you can find the offending machine if you try
Look in the DHCP leases for the MAC address of the error.

If possible, scan your network with Angryziber IP scanner (free) (google it) and scan your network, cross refrence this list against what DHCP and DNS say.
rcteryxAuthor Commented:
sorry, i meant the IP address corresponding to the offending IP is assigned through DHCP. that's how i found it.
check that sucker for malware and dialers, rogue vpn's something is causing the conflict
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Erik BjersPrincipal Systems AdministratorCommented:
Make sure the IP of your DCs is excluded from your DHCP scope (or reserved by the servers MAC addres)


rcteryxAuthor Commented:
the ip of the dc is not in the dhcp scope
Hi rcteryx,

is this just a warning or do you actually lose functionality? no DNS host conflictions?

Are you sure they are IP error conficts?  What is the exact working of the error message?

rcteryxAuthor Commented:
I figured it out. Somebody was bringing a computer on standby and his ip (assigned through dhcp) was coinciding with my DC's. I didn't think a home router would give out addresses that high.
Thanks for you comments.
good!  glad to hear things are working.  yes, alot of consumer routers begin their dhcp lease address scope at 100.
Erik BjersPrincipal Systems AdministratorCommented:
That's strange if this user was using DCHP for there IP they should have gotten a new one when connecting to your network...
If the laptop was on standby, then it would have already had a previous configuration.  When it was attached to the network and brought back online, it would have caused a conflict.
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