Permission re-activate error mac

I recently bought a new macbook pro, and now when I try to open unity I get this:

[13717-screen+shot+2013-07-30+at+10.05.14+am.png|13717]

I press re-activate and i get this message.
[13716-screen+shot+2013-07-30+at+10.02.40+am.png|13716]

Assistance would be much appreciated.

You have to deactivate the license on the old installation before you can use it on a new machine. This is done in the manage licenses dialogue in the original unity installation.

Ok great thanks