The company said it has reached the "release candidate" stage for Service Pack 1 of Windows Server 2003. Microsoft is also at a similar point with several 64-bit Windows versions that use the same code base, including Windows Server 2003 x64 Editions and Windows XP Professional x64 Edition.
Microsoft reiterated that all three products are slated for final release in the first half of next year, with a second release candidate in between.
A second update for Windows Server 2003, known as R2, is also planned for next year. Microsoft is shooting for a private beta of that release later this month, with a goal of having about 1,000 testers. The company said it hopes to release a public beta of R2 in the first half of next year, with the final release some time in the second half of the year.
For some time, Microsoft has been promising to deliver 64-bit versions of Windows to support AMD's Opteron and Athlon 64 processors, but final releases of the server and desktop operating systems were delayed until next year. The same version of Windows will also accommodate chips from Intel that support 64-bit extensions to the longstanding x86 architecture.
Microsoft said it hopes the new versions of Windows will help make 64-bit computing a mainstream activity by next year.
"There's a need for a mainstream 64-bit solution that is fast to deploy and easy to grow into," senior product manager John Borozan said in a statement. "Volume deployment of x64 will spur new opportunities for innovation that were previously limited by 32-bit barriers."
The biggest advantage of 64-bit computing today is the ability to directly access more than 4GB of physical memory.
Those who own a 32-bit version of Windows XP Professional or Windows Server 2003 will be able to exchange it for a license for the 64-bit edition, Microsoft has said.
Microsoft already has separate versions of Windows that support Intel's 64-bit Itanium processor, which has a completely distinct instruction set from the Opteron and the Athlon 64.
The release candidate for Windows Server 2003 SP1 is now available from Microsoft's site. The code for the 64-bit Windows versions is available now for those who take part in Microsoft's technical beta, or test, program. Within 30 days, Microsoft said, it will make the release candidate of those versions part of its Customer Preview Program.
The Windows Server update adds a number of the security enhancements Microsoft added to Windows XP with Service Pack 2. New features for Windows Server include an enhanced firewall, support for "no execute" hardware from AMD and Intel, and a new Security Configuration Wizard that blocks ports and services not being used by a particular server.
