Enable case sensitive behavior with Windows XP and Interix Subsystem or SFU (817921)

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256986 Description of the Microsoft Windows Registry

SYMPTOMS

If you use Interix 2.2 on a computer that runs Microsoft Windows XP, you cannot use files named like "abc.txt", "Abc.txt" and "ABC.TXT" in the same directory. This issue may also occur if you install Windows Services for Unix 3.0 and do not change the default behavior of Windows XP during SFU 3.0 setup. This issue does not occur if you use Window NT or Windows 2000.

CAUSE

By default, the Windows XP subsystems other than the Win32 subsystem are case-preserving but not case-sensitive. However, by default, in earlier versions of Windows the subsystems other than the Win32 subsystem are case-sensitive.

RESOLUTION

Warning If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To change the behavior of Windows XP after you install Windows Services for Unix or when you use Interix 2.2, you must add the following registry key, and then restart the computer:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Kernel

Value Name: ObCaseInsensitive
Data Type: REG_DWORD
Value Data: 0 (Case sensitive)

MORE INFORMATION

To support standard UNIX behavior, Windows Services for UNIX Setup permits you to change the default Windows XP behavior for non-Win32 subsystems when you install the base utilities (that install the Interix subsystem) or Server for NFS. If you turn on case sensitivity, and later remove Server for NFS and the base utilities, Windows Services for UNIX Setup restores the default, case-insensitive behavior of the non-Win32 subsystems.