As part of Microsoft's Customer Review Program, the RC version will be free to download and will be "available at least through June 30, 2009" with no limits on the number of downloads of product keys available.
Microsoft will collect feedback on the Windows 7 release candidate over the next few months, fixing small issues. The company allowed developers and other testers to begin downloading the release candidate last week.
Windows 7 comes nearly three years after Windows Vista, which took five years for Microsoft to engineer but was regarded by some as underwhelming. Microsoft hasn't said when the final Windows 7 version will be released, although it's rumoured to be out before year's end.
Microsoft warned it is not offering technical support for the Windows 7 release candidate, so those who install it are on their own. Users should be familiar with installing an operating system from scratch, formatting a hard drive and backing up data, among other skills, Microsoft advised.
In the Windows 7 release notes, Microsoft warns of several problems that haven't been resolved, including issues with its latest web browser, Internet Explorer 8 (IE8).
Microsoft released the Windows 7 beta in Arabic and Hindi, but those languages have been replaced with French and Spanish in the release candidate. English is available for both versions.
"We needed to ensure certain features were tested for worldwide functionality, and Hindi and Arabic help us test a number of language-related features," Microsoft said.
The Windows 7 release candidate will only work for so long. It is due to expire on June 1, 2010. Three months prior, the release candidate will automatically shut down a person's computer after two hours.
The Window 7 beta expires on August 1, and computers with that version will begin shutting themselves down after two hours beginning July 1.
Microsoft said that Windows Vista users will not need to reinstall their applications after upgrading to the Windows 7 release candidate. The company does, however, recommend backing up data as a precaution. Vista users will have to do a clean install, however, to go from the Windows 7 release candidate to the final version.
Windows XP users should back up their data and do a clean install of the Windows 7 release candidate.
To run the 32-bit version of the release candidate, a computer should have a 1GHz or faster processor, 1GB of RAM, 16GB of hard disk space and a DirectX 9 graphics processor with WDDM (Windows Display Driver Model) 1.0 or higher driver.
For the 64-bit version, Microsoft recommends a 1GHz or faster processor, 2GB of RAM, 20GB of hard disk space and a DirectX 9 graphics processor with WDDM 1.0 or higher driver.
When Microsoft launched the beta version of its latest operating system in January this year, it revealed it would restrict the preview to the first 2.5 million users, which caused a stampede that brought the company's severs to their knees.
Microsoft restarted the launch the next day after sorting out the mess and adding more bandwidth and servers. Later, Microsoft dropped the download limit and extended the time it would be available to a full month.
The RC version of Windows 7 was made available to subscribers of Microsoft's MSDN and TechNet services last week. However, heavy demand knocked the sites offline.
See also: Windows 7 release candidate in two weeks