Hi
Could you talk me through the steps you took to change it?
It was super easy to do on OS X, but actually trying it myself I see it's a little tricker in OS X 10.10. If you are on an older OS X, follow any of the many instructions you find online (it's a single line, the "sudo ifconfig" one). OS X 10.10 adds two more lines, in bold below:
1) Open up Terminal.app
2) Type
sudo /System/Library/PrivateFrameworks/Apple80211.framework/Resources/airport -z
Press return and then put in your password. It will not show you the letters •••• as you put them in.
3) Now change your MAC address using a terminal command along the lines of:
sudo ifconfig en0 ether my:ne:wM:AC:ad:dr
Press return. If you're quick it will not ask for a sudo password this time. (The MAC will also need to be in the format of a real hexadecimal number, see below.)
4) Now again, still in terminal, type
networksetup -detectnewhardware
press return.
5) An OS X prompt will come up, put your password in there too and hit OK.
6) Done.
You can validate this by typing "ifconfig" in Terminal and pressing return. On the line following en0: you should see "ether" followed by the number you put in above. If you do not, then it did not change your MAC.
It's possible that your device you use to connect to the Internet is not en0 (it might be en1 or even a higher number, though unlikely). To find this, type "ifconfig" in Terminal and hit return, then look for your LOCAL IP address. If you don't know your local IP, you can find this by going to System Preferences -> Network then looking at whichever you're connected with, WiFi, ethernet, etc. For instance mine right now is 192.168.1.103.
Anyway, once you have your local IP address, you can find which device you're using to connect to the internet by finding the line that looks like:
inet 192.168.1.103 netmask 0xfffff ...
Then look two lines above that one, which will say something like
ether 8c:d1:33:f1:d6:2f
This is the MAC address for the hardware device (wifi, ethernet, or whatever) that connects you to the Internet. Then look for the subheading one line above the ether line you just read. It will say something like:
en0: flags=8863<UP,BROADCAST, ...>
This ("en0" but could be "en1" or even a higher number) is the device that you want to change the MAC address. It's almost certainly en0 or en1 for you. When changing your MAC address, keep in mind that the new one must be in the format of a real MAC address (i.e. hexadecimal, using numbers 0-9 and the letters a-f, and must be 6 pairs of 2; in any case if you put something invalid it will complain).
When you change the MAC with the "sudo ifconfig en0 ether..." line, it's only temporary in that every time you restart your computer, it will revert back to the original MAC address. If this is a big issue you can set up a shell script / startup script that will change your MAC every time you reset, or even at more regular intervals if for some reason you really want the MAC to spoof all the time.
Also keep in mind that you can't have two devices with the same MAC address on the same network at the same time.
Also if you're just starting to learn command line, then make sure you understand what you're typing in if you're just copy and pasting from the Internet, especially if you're asking forums of people that are often dicks. Don't trust any command with "sudo rm" in it.
