Lets just say you replaced a dead motherboard, and now you have to re-active some old software that no one has the disc for, the company no longer supports and that is licensed by the MAC address of your network adapter.

Fortunatley, windows stores the old network adapter’s MAC adddres in the registry so you can assign it to the new network adapter and keep that old software runnin’

  1. Run regedit
  2. Navigate to;
    HKEY_LOCAL_MACHINE
    > SYSTEM
    > CurrentControlSet
    > Control
    > Class
    > {4D36E972-E325-11CE-BFC1-08002BE10318}
  3. There is a subfolder for each network adapter (or connection) that has been in the computer, click on each to see the description and when you find the right one, look for a Key called “Network Address” which contains that adapters’ MAC
  4. Celebrate and assign to the new adapter

*Note, I’ve seen this NOT be present on some windows 7 installs but if you’re working on a computer THAT old, it’s probably XP.

Thanks to Chris Daniels for the tip