Microsoft quietly delivered a first private beta release of Windows Server "R2" to the first of about 1,000 testers on Wednesday, company officials confirmed Friday.

Meanwhile, Microsoft is soliciting a wider pool of beta testers for a second R2 beta, which it is planning to deliver in the second quarter of 2005, said Bob Muglia, senior vice president of Microsoft's Windows Server division. Microsoft is telling these testers to expect the final release of R2, the follow-on to Windows Server 2003, to ship in October 2005.

Microsoft is laboring on a number of other R2-related releases besides the full-fledged server release, Muglia said. The company also is working to deliver a first beta of Windows Small Business Server R2 in the coming months. And earlier this fall, Microsoft released to select OEM testers a first beta of Windows Storage Server R2, Muglia said.

R2 is a fairly minor version of Windows Server that will be built on the Windows Server 2003 Service Pack 1 (SP1) code base. It will include a number of the myriad Windows Server 2003 feature packs that Microsoft has shipped since April 2003. Earlier this fall, Microsoft officials said they planned to cut a few key features slated for R2, including network-access protection and file sharing over HTTP, in order to make its planned 2005 ship date.

R2 will feature a new file migration toolkit; simple-SAN management tools; a new storage-resource-management subsystem (code-named "Corral"); and centralized file and print management facilities aimed squarely at corporate branch-office customers.

Muglia reiterated on Friday that Longhorn Server, the follow-on to R2, is still on track for 2007. Like R2, Longhorn Server is being built atop the Windows Server 2003 SP1 code base, he said. Windows Server 2003 SP1 entered the "release candidate 1" beta phase on Monday. Microsoft expects the final version of SP1 to go gold in Q1 of 2005, Muglia said.