I have been using the Windows 7 Enterprise 90-day Trial edition and as some may know one can 'rearm' the trial something like 3 times after it expires.
In order to do so you simply run the following from a command prompt with administrator rights (right click the cmd link and click on 'Run as administrator'):
Well. It didn't work. It wouldn't rearm. Some folks reckon after the trial expires you are shafted and some reckon you need to reboot a couple of times. Others go with a crack approach. Then I came across this:
And that did the trick. So you need to run both. The first seems to do the 'rearm' bit and the second the activation.
Man am I happy. I hope this helps someone else out there.