Microsoft has revamped its pricing model for the next version of Windows Small Business Server (SBS) in a move which the software giant says will lower the overall purchase costs for some smaller businesses.

The company has also delivered a public preview, Release Candidate 0 (RC0), of its forthcoming Essential Business Server 2008 software.

Due later this year, SBS 2008 integrates Windows Server 2008, Exchange Server 2007, Windows SharePoint Services (WSS) and SQL Server 2008 (Premium Edition only), and includes five client access licences (CALs) as standard.

Whilst Microsoft has increased the initial purchase cost of SBS 2008 compared to SBS 2003, it has lowered the price of each additional CAL, which can now be purchased one at a time rather than in increments of five.

Windows Small Business Server 2008 Standard Edition is 64-bit only and will
now cost $1,089 (£561), up from $599 (£308) for SBS 2003, with each additional CAL priced at $77 (£40) instead of $90 (£46).

Whilst savings look possible for smaller companies using the Standard Edition of the product, specifically depending on the number of CALs they require, the same does not appear to be true of the Premium Edition. Available in either 32- or 64-bit versions, this will add the SQL Server database product and a second copy of Windows Server 2008, and costs $1,899, up from $1,499 for the Premium Edition of SBS 2003, with additional CAL costing $189, up from $90.

Microsoft also says that Essential Business Server 2008, a new product due in the second half of 2008, can cost up to a third less than buying individual versions of the software it includes: Server 2008, System Center Essentials, Exchange 2007, and SQL Server 2008 (Premium Edition only).

It will also feature enhanced security tools including Forefront Security for Exchange, Exchange 2007 Edge Services, and Forefront Threat Management Gateway (TMG) for Medium Businesses – formerly called ISA Server.

Windows Essential Business Server 2008 Standard Edition will cost $5,472 and additional CALs $81 each. The Premium Edition with SQL Server included bumps the price to $7,163 with additional CALs costing $195 each. Both Editions are 64-bit only.

Customers can download the RC0 of Essential Business Server 2008 from the Microsoft website, with SBS 2008 RCO expected to be available in the next two weeks.