Microsoft will soon put the screws to those still running last year’s free preview of Windows 7 by incessantly shutting down their PC.

Starting on February 15, Windows 7 Release Candidate will begin displaying a friendly notice every few hours to either get paying or get bent. Come March 1, the PC will begin a regiment of automatic, bi-hourly* shutdowns to drive home the message.

Escape from the harassment will only come after a clean install of a paid-for copy of Windows. The company has previously stated, however, that users can use an upgrade edition of Windows 7 to move from the RC to a release copy.