I want to do this every 30 minutes or so.
Create a mac address random and disable the network adapter and then enable the network adapter for the mac address change to take.
Any ideas?
Thanks. Why do you need to do this?
I change it now freq.
Manual is a pain if I can make it auto.

I used to buy network CARDS monthly, SWAP them out with the new and throw the old ones out.
I run a game server.
Uncomplicates my life.Try this

You need to change a registry key like so

reg add HKLM SYSTEM\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002BE10318}\0001] /v NetworkAddress /d 0123456789AB

Replace 0001 with your interface number and 0123456789AB with desired network address.

Next, disable and enable the network card

Subsitute the actual network connection name if it isn't Local Area Connection.

netsh interface set interface "Local Area Connection" DISABLED
netsh interface set interface "Local Area Connection" ENABLED

You didn't say what Windows you are using. I think the netsh part may not work on XP and earlier.

win 7.
Thank you.You really must be sure you know what you are doing before you mess with the registry. It sounds like a working network connection is important to you (as it is to most PC users these days) so give yourself a route back - backup registry, take a note of the subkeys under that registry key etc.