The warning box was popping up every hour until only 1 hour remained, it was then I took action,  backed things up and installed afresh Windows 7 on two machines at home. This of course was the warning  preceding the bi hourly shutdown of the release candidate, build 7100, which was made available as a try-out to the general public on May 5, 2009. The release candidate fully expires on June 1, this year. It was nice using for free what is undoubtedly the best windows incarnation so far.


Contrary to Microsoft stating you have to install afresh, you can actually upgrade the Windows 7 Release Candidate, but it may not be advisable as you might have to run a repair install in the future.