MAC address

Eglinton

Could anyone tell me if the MAC address of the NIC should change if you format a hard drive and reinstall XP

raphaelS

No, each card has its MAC address and it won't change depending on the OS or machine... generaly there's a sticker on the card with the number.

Now, maybe you can change the Mac address but I guess you would need to hack into the firmware...?!

Raphael

zAbbo

Such a silly question, no the MAC wont change.

To view your mac:

Start > Run > cmd > ipconfig /all

And its the physical address

po0k

Originally posted by raphaelS
No, each card has its MAC address and it won't change depending on the OS or machine... generaly there's a sticker on the card with the number.

Now, maybe you can change the Mac address but I guess you would need to hack into the firmware...?!

Raphael

The MAC address is transmitted through a layer of software and can easily be spoofed.

Eglinton

it can definitely be changed. Mine did.

zAbbo

Yes it can be changed, no it wont change with a re-install

Eglinton

it did change with re-install. its al laptop so maybe its somekind of "soft" card

Ryaner

The mac addresses are burnt into the card to provide a safe way to filter on networks. The actual card mac address cant be changed per say. The card will still have the same address no matter what you do.
Because it is reported to the os, and then the network though a software layer it can be spoofed as SyxPak said. It very to do. There are quite a few apps around to change the address on the fly

Eglinton

Do you know how i can put it back to the original so i can re-connect to the network

Ryaner

If your not spoofing the address yourself then it's very unlikely that it's changed to a different address and that the problem is somewhere else.

moridin

Unless, as someone posted, it's a piece of crap built in card that uses uber-software drivers.

Ryaner

Even the built in cards have a hardburned mac address on them.

moridin

They should have, but if the guy is saying his MAC address has changed, and all he's done is reinstall, then re-iterating standard literature on what how they're not supposed to change isn't going to help him.

To get back on topic:

I assume this is for a wireless network where you need to hand in your addy to a computing department or something... perhaps the best idea would be to speak to them and tell them what's happened.

Occidental

Is it possible that your MAC address before the re-install was spoofed and that you have now reverted to the burnt in address. If so then you will need to have a talk with whoever runs your network. Hopefully if it's a wireless network, they're not using MAC addresses as their sole form of security.

Ryaner

I agree that talking to the who ever admin's the network to see about getting back on.
The other thing you could do is if you know the old mac address that simply spoof it and you'll be back on.

Capt'n Midnight

Some NIC's have SW utils to change the MAC address on the card (rare)
The first 3 bytes of the MAC address are for the manufacturer and the last 3 bytes for the "serial no."! of the card. Thus ALL are unique. IIRC at least one manufacturer had to buy back old NIC's so they could reuse the serial numbers on new cards !

ifconfig - will allow you to change the MAC address reported by the network card driver in Linux.

Note: some NIC's have firewall software, and devces like Ethernet converters, Firewalls, Ethernet modems can usually adopt the MAC of the PC they are connected to or you can enter a reserved address.

Note2:When you use a modem in windows it uses a MAC address.

Mac daddy

have a look here