Annoying exchange server 2003 problem

[eidolon]

My exchange server has the IP address of 192.168.0.2 and every few days around 9.15ish it has an IP conflict which causes it to go offline for a few mins while it sorts itself out.

The system detected an address conflict for IP address 192.168.0.2 with the system having network hardware address 00:16:6F:81:8C:1A. Network operations on this system may be disrupted as a result.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

I can't seem to find anything on the network with that mac address and everything else on the network has DHCP assigned IP addresses starting from 192.168.0.100 so nothing should be trying to get the 0.2 address.
I can only assume that somebody is bringing a device into the building which has a static IP of 0.2 and that is trying to join the network and confusing the exchange server.

It'll be a nightmare trying to audit every possible device that people could possibly bring into the building so has anyone got any ideas?

 

[eidolon]

I've got a feeling it must be a wireless device, could be a phone, PDA, laptop or something.
I don't think I can get anything off the switches as they're not managed ones or anything. I've tried using a piece of software which scans the network for mac addresses but whatever device it is seems to disappear as soon as it is refused the 0.2 IP address.

For now I've just blocked the mac address on the wireless APs so I'll see if that helps.

 

[eidolon]

Aha, making progress now.

I just received a call from a laptop user that couldn't connect to the network. A quick check and he is indeed the owner of the above mac address.
His wireless settings are fine however, just assigned an address via DHCP but I did notice that he was running activesync which I think is the problem.

Not entirely sure what I need to configure yet but for now I've just changed the auto connection configuration to manual in Active sync.

Fingers crossed!