why would you want to change a MAC address?

Answer 1

The guy before me is wrong, you can change the MAC address. Though it does not actully change it, it just makes windows and other computers think it is changed (i.e. if you reformat the computer or stick the NIC in a new computer, it will revert back to its normal MAC address.

You can change it with some registry modifications or a program called SMAC.

Answer 2

An IP address is your address to the network of networks, the internet .... it gets your data to the right network ... but a MAC address is what gets your data to your computer when it gets to your network. All the devices on a network talk to each other based on mapping their IP addressed to their MAC addresses.

MAC addressed have to be there because not every network is based on ethernet, and you want something permanently built into your computer that other computers cannot just steal and pretend to be your computer.

That said, some systems have progammable MAC addresses.

This is useful because it does occasionally happen in large networks that through a screwup two computers end up with
the same MAC address, and if they are on the same subnet neither will work right.

So to fix that very rare situation it is useful to have your MAC address be able to be changed.

Answer 3

You cannot have same MAC in more than one computer within one network, so that is why you want to change, and saying not possible to change is wrong, but you need a DOS boot floppy and a manufacturer utility program.

Answer 4

MAC addresses are assigned at the factory when the NIC is manufactured.

Next to impossible to change without specialized equipment.

Answer 5

You cannot change a MAC address it's unique to each ethernet/wireless adapter.

You can change their ip address though.

Answer 6

to get past a filter, or to authenticate on a network that MAC filter.

Answer 7

To stay anonymous