The clock is ticking for those that want to play around with the Windows 7 beta.
Microsoft issued a late reminder on Monday that people had only until midnight Pacific time to start downloading the operating system.
Those who started their download in time have until 9 a.m. PST Thursday to finish the process, Microsoft has said. Those who went to the site on Tuesday were able to get a product key, but not the code itself.
"We're sorry, but downloads are no longer available," Microsoft says when users click through from the download page.
Although the beta version will cease being available to the general public, members of Microsoft's MSDN and TechNet developer programs will continue to have access to the code.
The software maker has said the next test version of Windows 7 will be a near-final "release candidate" version, although it has not said when to expect that to arrive. Officially Microsoft has said that the final version of Windows 7 will come by the end of January 2010, although the company has been aiming to get it done in time to be on PCs that ship for this year's holiday-shopping season.