Those who signed up to run a free copy of Windows 7 are about to see their computers getting cranky. Microsoft was onto a winner when it gave away millions of copies of Windows 7 RC for people to play around with until March.

The big idea is they would use it, find out how good it was, and buy a copy of the final version. Microsoft warned that in March the computer would start to shut down every two hours and on June 1, the screens will go black.

All seems reasonable to us, after all you have had plenty of warning, however there are mutterings that by doing this Microsoft may have done something wrong. The problem is that buggering around with the OS also stuffs up customers' data.

The problems of loss of control over a person's computer to satisfy a software company is also not been tested in law yet. While lots of software has shut off codes in it, software often is only going to control one sort of data. If your operating system goes down you lose the lot. That is if you are dumb of course. But a lot of court cases are based on protecting the terminally dumb and it will be interesting to see if someone tries to get Microsoft on this one.

However if you were clued up enough to download the RC candidate, now is probably the time to back up your files and splash out and  buy another operating system. Of course you can always go the other way and just download something open saucy.