Find the MAC address of the DHCP Server (rogue router)

The person experiencing the problem on the computer having the issue will need to do the following:

  1. Go to a DOS/Command prompt (Start > Run > cmd).
  2. Type ipconfig /all
  3. Look for & record the IP# of the DHCP Server (won't be a 128.255...)
  4. Ping the above discovered DHCP IP# (by typing ping space then ip number)
  5. Type ARP -a
  6. Look for the MAC address that corresponds to the above DHCP IP#
  7. Call the ITS Help Desk and give them this MAC address you received as a result from the ARP command.
Article number: 
Last updated: 
November 7, 2012