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If you can find the machine as per above, I find that people sometimes set laptops to static IP addresses for their home setup. Then I have found conflicts when they bring the machine to the office. <br />
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Also look for USB Internet keys. My HUAWEI key broadcasts Wi-Fi (but I have it secured so nothing picks it up).
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Do you have the 2008 server running wirless aswell?<br />
I would find out what ever device is on the network is and turn off DHCP on the other devices and have the server assign the ip's or what device you have as your DHCP SERVERS.
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If you have IP and MAC address and switches with management you can find to what port is this machine connected from MAC table in the switch.
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Most of the time this is due to IP conflicting will not show you conflict message most of the time.. instead it will switch to automatic IP address.. <br />
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You must resolve duplicate IP addresses already &nbsp;assigned (Which leads to a conflict ).That will fix the issue.<br />
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DON’T use netsh winsock reset command as it wont fix this until you resolve duplicate IP issue .Restarting /disabling and enabling Ethernet connection nothing will fix..<br />
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There could be many ways to resolve IP conflict. If you have manually assigned IP addresses, you have to check and eliminate duplicate IPs &nbsp;<br />
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Most of the time this issue is prevalent, where there is an environment with manually assigned IP addresses and DHCP server and dhcp clients..
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Stretching my brain here to offer an option not already provided..<br />
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Have you tried to RDP to the offending IP to see if you can get a logon prompt? (RDP would need to be enabled already on the offending machine)<br />
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If so, check the name of the device and find it from there by seeing the currently logged in User, or the logon name that appears by default. Or, switch User and see what the name of the PC is. If it is in your network you will probably know whose it is by the name.
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APIPA address 169.254.x.x guides us that your server configured with a dynamic addressing AND couldn't get IP from DHCP server .<br />
1.from the server : try to ping your DHCP server then when you can ping it start to resolve problem from this point .<br />
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Advice : you had better configure your servers with STATIC IP .<br />
2.if you need to hunt a rogue DHCP try (Wireshark,DHCP Explorer,DHCP detector,Roadkil's DHCP Find) and search about DHCP SNOOPING .<br />
best regards
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Firstly, why is your fileserver on DHCP and not a static IP?<br />
<br />
Secondly, getting a 169.254.x.x address doesn't necessarily mean there is a conflict, it usually it couldn't get an address from DHCP in the first place.<br />
A conflict usually shows as an error or 0.0.0.0 in IPCONFIG.<br />
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I'd check your DHCP server's logs to check DHCP is working OK and also make sure the fileserver can contact it OK. if it cannot see the DHCP server it will get a 169 address.<br />
If there is a conflict, the DHCP server should log it as a conflicting IP. This usually only happens if 2 DHCP servers are giving out the same IPs or if someone has set a static IP in the middle of your DHCP range.<br />
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If this all looks OK, check reservations in DHCP in case two machines have been given the same reservation IP.
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<div class="content wysiwyg-content">
I have a 2008 R2 AD network and our fileserver keeps getting a .169 address after reboot because of a duplicate IP address. &nbsp;<br />
<br />
This IP is not being handed our through dhcp or through the normal wireless it seems. &nbsp;Maybe it's coming from a rogue wireless network by a phone or laptop? &nbsp;I set the server temporarily to another address and it works for shares, printing and backups but is not a good long term solution. &nbsp;I have the IP and the mac address of the rouge machine. &nbsp;<br />
<br />
What can I do to quickly and permanently eradicate the issue?<br />
<br />
Please help!<br />
<br />
MF
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I have a 2008 R2 AD network and our fileserver keeps getting a .169 address after reboot because of a duplicate IP address.  

This IP is not being handed our through dhcp or through the normal wireless it seems.  Maybe it's coming from a rogue wireless network by a phone or laptop?  I set the server temporarily to another address and it works for shares, printing and backups but is not a good long term solution.  I have the IP and the mac address of the rouge machine.  

What can I do to quickly and permanently eradicate the issue?

Please help!

MF

Duplicate IP address on network

Network analysis is the process of identifying and remediating the processes and systems within a network, including performance, connectivity and security. The process is performed through the use of tools developed for monitoring and analyzing network activity. Network problems that involve finding an optimal way of doing something are studied under the name combinatorial optimization. Examples include network flow, shortest path problem, transport problem, transshipment problem, location problem, matching problem, assignment problem, packing problem, routing problem, Critical Path Analysis and PERT (Program Evaluation & Review Technique).

Network Analysis

Windows Server 2008 and Windows Server 2008 R2, based on the Microsoft Vista codebase, is the last 32-bit server operating system released by Microsoft. It has a number of versions, including including Foundation, Standard, Enterprise, Datacenter, Web, HPC Server, Itanium and Storage; new features included server core installation and Hyper-V.

Windows Server 2008

The Windows operating systems have distinct methodologies for designing and implementing networks, and have specific systems to accomplish various networking processes, such as Exchange for email, Sharepoint for shared files and programs, and IIS for delivery of web pages. Microsoft also produces server technologies for networked database use, security and virtualization.