Notice: This website is an unofficial Microsoft Knowledge Base (hereinafter KB) archive and is intended to provide a reliable access to deleted content from Microsoft KB. All KB articles are owned by Microsoft Corporation. Read full disclaimer for more details.

POSIX and OS/2 are not supported in Windows XP or in Windows Server 2003

View products that this article applies to.

This article was previously published under Q308259

↑ Back to the top


There is no support for POSIX or OS/2 programs in Microsoft Windows XP-based or in Microsoft Windows Server 2003-based operating systems.

↑ Back to the top

More information

POSIX support

The Portable Operating System for UNIX (POSIX) subsystem is not included with Windows XP or with Windows Server 2003. The POSIX subsystem has been replaced with a more UNIX-like environment that is named Windows Services for UNIX. Windows Services for UNIX is a superset of the original POSIX subsystem and provides greater functionality for UNIX programs. Windows Services for UNIX requires Windows XP Professional Service Pack 1 (SP1) or later.

For additional information about Windows Services for UNIX, visit the following Microsoft Web site:

OS/2 support

The OS/2 subsystem is not included with Windows XP or with Windows Server 2003. An alternative solution for OS/2 programs is Microsoft Virtual PC 2004. Virtual PC 2004 supports most OS/2 programs including OS/2 programs that have a graphical user interface (GUI).

For more information about Virtual PC, visit the following Microsoft Web site:

↑ Back to the top

Keywords: KB308259, kbinfo, kbenv

↑ Back to the top

Article Info
Article ID : 308259
Revision : 11
Created on : 11/5/2007
Published on : 11/5/2007
Exists online : False
Views : 250