Mengganti MAC Address di Windows XP
Untuk beberapa keperluan tertentu biasanya ada aplikasi di jaringan yang membaca MAC Address di network card PC kita. Biasanya yang menggunakan hot spot yang ada di public hal ini sering terjadi or kalo mo 'hacking' 
joule juga dapat info ini dari internet mudah-mudahan bermanfaat.
Cara mengganti MAC address
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.
a) Go to Start->Settings->Control Panel and double click on Network and Dial-up Connections.
b) Right click on the NIC you want to change the MAC address and click on properties.
c) Under “General” tab, click on the “Configure” button
d) Click on “Advanced” tab
e) Under “Property section”, you should see an item called “Network Address” or “Locally Administered Address”, click on it.
f) 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.
g) 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.
h) If successful, reboot your system.
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