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SMAC 1.2
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SMAC - MAC Address Modifying Utility for Windows 2000 and XP systems.

By KLC Consulting (KLC) Security Team,
Kyle Lai, Senior Security Consultant,
Bob Bourret, Senior Software Developer


Thank you for purchasing SMAC.


SMAC Official Website is at http://www.klcconsulting.net/smac.


Table of Contents:


Description:    (back to Top)

SMAC is a powerful, yet an easy-to-use and intuitive Windows MAC Address Modifying Utility.  SMAC allows users to change MAC address for any Network Interface Cards (NIC) on the Windows 2000, XP, and 2003 Server systems, regardless of whether the manufacturers allow this option or not.

SMAC does not change the hardware burned-in MAC addresses.  It is not necessary.  SMAC changes the "software based" MAC addresses on the Windows 2000, XP, and 2003 Server systems, and the new MAC addresses you change will sustain from reboots.

SMAC is created by Certified Information Systems Security Professionals (CISSP), Certified Information Systems Auditors (CISA), Microsoft Certified Systems Engineers (MCSE), and professional software engineers.  With combined efforts, SMAC is well designed to be an user-friendly tool for both the technical and non-technical users.

Please submit bug reports and your wish list to us (smac@klcconsulting.net).


Features:    (back to Top)

  1. Easy, user friendly GUI for viewing and changing MAC addresses.

  2. Displays all NIC's device ID, Status, NIC description, spoofed (Yes/No), IP, and active MAC addresses.

  3. Users can choose to display detailed information of all available adapters, or ONLY the active network adapters.

  4. Built-in logging capability for you to track MAC address modification activities. 
    (Of course you can delete the log file at any time.)

  5. Supports Windows 2000, XP, and 2003 systems in all languages.

  6. Provides View Log option (menu File->View Log) to view SMAC activity log from within the SMAC GUI.

  7. Provides "Clear New Spoofed MAC Address" button (X)

  8. MAC address activation required notice is displayed after a MAC address is updated.  Users have the option to turn this message off via a checkbox.


Installation:    (back to Top)

Install SMAC 1.2:

  1. If a previous version was previously installed, uninstall the previous version by going to "Control Panel -> Add/Remove Programs."  (Log file will not be deleted.  If SMAC 1.2 is installed to the same folder as a previous version, the SMAC log will be reused.)

  2. Install SMAC 1.2.

    1. Run "setup.exe" to install SMAC.


System Requirements:    (back to Top)

  • SMAC 1.2 Works on Windows 2000, XP, 2003

  • SMAC works on Network Interface Cards (NIC) that are on the Microsoft Hardware Compatibility List (HCL).  Usually you will see a "Designed for Windows 2000" or "Designed for Windows XP" logo on the box of the NIC.  If your NIC is not on the HCL, please contact your NIC manufacturer to check for compatibility.


Usage Guide:    (back to Top)

  • SMAC 1.2 has 2 modes of operation:  [WBEM ON] and [WBEM OFF].  The mode of operation is shown on the top left corner of the window.

    If you have the “Windows Management Instrumentation (WMI)” service running, it will be running on [WBEM ON] mode.  Otherwise, it will be running on [WBEM OFF] mode.  WMI service is shipped with Windows 2000, XP, and 2003, and WMI is started automatically by default.  In SMAC 1.2, [WBEM ON] mode shows more network adapter information. 

  • After you update (modify) a new MAC address, in order to make the new MAC address active, you must activate the new MAC address.  You do this by disable then re-enable the network adapter, or reboot your system.  Please refer to Activate New MAC Addresses section for more details.

  • SMAC 1.2 also provides logging capability to track SMAC MAC Address modifying activities.  The log file is located in the same directory as the SMAC program file.


Descriptions of information displayed:




Network device ID


Indicates whether a network adapter is configured and available for use.


Contains spoofed MAC address in the registry

Network Adapter

Description of Network Adapters

IP Address

Assigned IP address

Active MAC

Active MAC Address for the Network Adapter


  1. “Spoofed” column determines if there is a spoofed MAC address entry in the registry.  This column does NOT indicate whether the Active MAC is spoofed.

  2. “Active MAC” column may or may NOT contain the true hardware MAC address.  If there is a spoofed MAC address is in the registry during the system boot-up process, then removed after the system is boot-up, there is no easy way to determine if the current MAC address is spoofed unless using vendor specific network adapter device drivers.  Therefore, SMAC does not show if the Active MAC is spoofed or not.




“Show Only Active Network Adapters” checkbox

When the checkbox is checked, SMAC will display only the network adapters that are configured and available for use.

"Remove MAC" button

Remove the spoofed MAC address for the selected Network Adapter.

"Update MAC" button

Update the new spoofed MAC address into the registry for selected Network Adapter.

"Refresh" button

Refresh the List with current information.

"Exit" button

Exit SMAC program.

Arrow button ( D )

Move the adjacent address to the “New Spoofed MAC Address” entry area.

Clear New Spoofed MAC Address button (X)

Clear the New Spoofed MAC Address

"Spoofed MAC Address" field Shows the current spoofed MAC address registry entry for the specified network adapter.
"Active MAC Address" field Shows current active MAC address for the specified network adapter.


Activate New MAC Addresses:    (back to Top)

There are 2 ways to make the newly changed MAC addresses active.  Method I does not require a system reboot.:

            I.     Go to Start->Setting->Control Panel, and double click on "Network Neighborhood". 

WARNING: Make sure you understand that you WILL lose the network connection after completing step "2." below.  If you are a DHCP client, you might get a new IP address after completing step "3."

1.     Select the Network Adaptor for which you want the MAC address changed.

2.     Right click on the selected Network Adaptor and click "Disable."  Verify that the status column for this adaptor has changed to "Disabled"

3.     Right click on the selected Network Adaptor and click "Enable."  Verify that the status column for this adaptor has changed to "Enabled"

4.     If for any reason the network adapter cannot be disabled or re-enabled, you will have to reboot your system to make the changes effective.

          II.     Reboot your computer.  

True Hardware Burned-in MAC Address:    (back to Top)

In order to get the True Hardware MAC address, you must remove the spoofed MAC entry from the registry.  Here are the steps:

  1. Select the specified network adapter
  2. Click "Remove MAC" button
  3. Disable and re-enable the network adapter, or just reboot the system.
  4. Refresh SMAC to display true hardware burned-in MAC address for the specified network adapter.



  1. Make sure you DO NOT assign one MAC address to multiple NIC's on a Local Area Network (LAN).  Doing so may cause network problems.  MAKE SURE YOU HAVE ONE UNIQUE MAC ADDRESS PER NIC!!!

  2. You must assign MAC addresses according to the IANA Ethernet-number assignment database.

  3. Make sure you DO NOT use Multicast MAC addresses.  You can check out the Multicast MAC addresses at http://www.iana.org/assignments/ethernet-numbers.

  4. "00-00-00-00-00-00" is NOT a valid MAC address.  Even though you spoofed your MAC address to "00-00-00-00-00-00," your network adapter will reject this MAC address, and your TRUE MAC address will remain.  Otherwise, your network adapter may not function.   

  5. In order to activate the new MAC address, you need to disable then re-enable the network adapter, or reboot your system.



How to contact KLC Consulting, Inc. (KLC):    (back to Top)

KLC Consulting, Inc.
P.O. Box 395
Holden, MA 01520

For more information about KLC and our services, please visit KLC website at http://www.klcconsulting.net or send us an email to info@klcconsulting.net



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