Deauthorized DHCP Servers Still Listed

I’ve run into the situation several times in the past where you deauthorize a DHCP server/scope, but when you click on “Add Authorized” server in your DHCP MMC snap-in, it still lists the old servers. I’ve found the quickest and most efficient way to remove these servers is using ADSIedit.

  1. Click start, in the search box type MMC and hit enter.
  2. On the console screen that pops up, add ADSIEdit to your list of snap-ins.
  3. Right Click “ADSI Edit” and select “Connect to…” from the menu.
  4. Leave all defaults except the “Select a wekk known Name or Naming Context”. Hit the drop down arrow and select Configuration and then click OK:

  5. Drill down to CN=NetServices and highlight it:

  6. Double click on CH=DhcpRoot.

  7. Scroll down until you find the dhcpServers attribute. Double click on that attribute and remove the offending servers from the value field. Apply and close and you’re done!