Extending the Windows Vista trial to 120 days from 30 days Windows Vista is the .NET developers platform. It supports .NET from the start and in the coming years I believe Windows Vista will be what causes many developers to start switching development from the standards Windows API's over to .NET and it's libraries as the install base grows.

With that though, I'm sure there are still many developers that just haven't got around to upgrading to Vista so Coding Horror had this great post on how to extend the Windows Vista trial to 120 days which is 90 days more than the original trial allows. I don't actually know if this was intentional by Microsoft and this will be fixed with a patch later but hopefully this remains a feature.

No hacks required. This is an official, supported operation directly from Microsoft.

To extend the grace period another 30 days, simply start a command prompt as Administrator, and issue this command:

slmgr -rearm

Reboot for the change to take effect, and voila, you have 30 more days. You can only extend three times, so the total grace period for a Vista evaluation is 120 days. You do, however, need to be careful that you've installed the correct edition of Vista. At the end of that 120 day grace period, you'll have to pony up a license fee for the edition of Vista you've installed.

I will definitely be trying this in the next week or so. Now all I need to do is find a link for the download of Windows Vista trial.  ¶ 9:14 PM