Microsoft Corp duly unveiled its Microsoft BackOffice integrated networking system: the Windows NT Server 3.5 began shipping yesterday, while the SQL Server and SNA Server will begin shipping within a couple of weeks; the Systems Management Server follows by November 30, the Mail Server is already available; servers and clients will be licensed independently so that users can pay only for what they actually add, either more clients or more servers; Windows NT Workstation 3.5 costs about $320, NT Server 3.5 is $40 for each client access licence and $700 for a server licence; SNA Server 2.1 is $65 for each client access licence, $410 for a server licence; SQL Server 4.21a is $190 for each client, $1,500 for a server licence, and Systems Management Server 1.0 is about $55 client, $650 server and the full BackOffice is $310 for each client, $2,200 for a server.