Changing the MAC address in W2K and XP

Method 1:

This is depending on the type of Network Interface Card (NIC) you have. If you have a card that doesn’t support Clone MAC address, then you have to go to second method.
1. Go to Start->Settings->Control Panel and double click on Network and Dial-up Connections.
2. Right click on the NIC you want to change the MAC address and click on properties.
3. Under “General” tab, click on the “Configure” button
4. Click on “Advanced” tab
5. Under “Property section”, you should see an item called “Network Address” or "Locally Administered Address", click on it.
6. On the right side, under “Value”, type in the New MAC address you want to assign to your NIC. Usually this value is entered without the “-“ between the MAC address numbers.
7. Goto command prompt and type in “ipconfig /all” or “net config rdr” to verify the changes. If the changes are not materialized, then use the second method.
8. If successful, reboot your systems.
Method 2:

This method requires some knowledge on the Windows Registry. If you are not familiar with Windows Registry, just use the SMAC tool to change the MAC addresses, or consult with a technical person before you attempt on the following steps. Also, make sure you have a good backup of your registry.

a. Goto command prompt and type “ipconfig /all”, and

I. Record the Description for the NIC you want to change.

II.Record the Physical Address for the NIC you want to change. Physical Address is the MAC Address

b. Goto command prompt and type “net config rdr”, and you should see something like.



c. Remember the number between the long number (GUID) inside the { }. For example, in the above “net config rdr” output, for MAC address “00C095ECB793,” you should remember {1C9324AD-ADB7-4920-B02D-AB281838637A}. You can copy and paste it to the Notepad, that’s probably the easiest way.

d. Go to Start -> Run, type “regedt32” to start registry editor. Do not use “Regedit.”
e. Do a BACKUP of your registry in case you screw up the following steps. To do this
I. Click on “HKEY_LOCAL_MACHINE on Local Machine” sub-window

II. Click on the root key “HKEY_LOCAL_MACHINE”.

III.Click on the drop-down menu “Registry -> Save Subtree As” and save the backup registry in to a file. Keep this file in a safe place.

f. Go to “HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318}. Double click on it to expand the tree. The subkeys are 4-digit numbers, which represent particular network adapters. You should see it starts with 0000, then 0001, 0002, 0003 and so on.