Microsoft has released Windows Vista Release Candidate 1 to the general public. The software was released to a limited group of testers earlier this month. 

The latest test version is available in English, German and Japanese for 32-bit and 64-bit systems.

Microsoft plans to issue a limited number of product activation keys, but a spokesman was unable to specify how many.

The software giant anticipates that five million people will have a chance to evaluate the software. This number includes roughly 500,000 IT professionals and developers who received access to the software on 1 September.

Vista Release Candidate 1 will expire on 1 June 2007, at which time users will be required to install the final version of Windows Vista or downgrade to Windows XP.

Microsoft warned that Release Candidate 1 should not be used in a production environment or on the primary computer at home.

Users also might not be able to upgrade the Windows Vista RC1 installation to the final commercial version of the operating system.

The software is available for download from the Microsoft Vista website or testers can order a DVD at a small fee to cover production and shipping costs.