Here's the help information from Windows Services for UNIX -
Case sensitivity and system security
If you are installing Windows Services for UNIX on Windows XP or
Windows Server 2003 family, you might be required to choose whether to
change the default behavior of object names such as file names to
being case sensitive. The choice you make will affect system security
as well as how Windows Services for UNIX functions.
In Windows, the names of most objects (such as files and directories)
are case preserving, but case insensitive. That means you can use
uppercase and lowercase characters when naming such objects, but
Windows does not distinguish between names based on case alone. For
example, you cannot have two files in the same directory named
sample.txt and Sample.txt because Windows regards the names to be
identical for the purposes of identifying files. The UNIX operating
system, on the other hand, is fully case sensitive, and so UNIX
computers distinguish between object names when the only difference
between those names is the case of characters used in the object
names. On most UNIX computers, therefore, sample.txt and Sample.txt
could appear in the same directory, and the UNIX computer would
distinguish between them when performing operations on the files. For
example, the command rm S*.txt would delete Sample.txt but not
sample.txt.
In order to implement typical UNIX behavior, the Server for NFS and
the Interix subsystem are normally case sensitive when working with
file names. This can present security issues, particularly for Windows
users who are accustomed to the case-insensitive conventions of
Windows. For example, a Trojan horse version of edit.exe named
EDIT.EXE could be stored in the same directory as edit.exe. If a user
were to type edit at a Windows command prompt, the Trojan horse
version (EDIT.EXE) could be executed instead of the standard version.
If case sensitivity is enabled, Windows users should be made aware of
this possibility.
In Windows XP and Windows Server 2003 family, the default behavior of
subsystems other than the Win32 subsystem is to be case preserving but
case insensitive; in previous versions of Windows, such subsystems
were fully case sensitive by default. In order to support standard
UNIX behavior, Windows Services for UNIX Setup allows you to change
the default Windows XP and Windows Server 2003 family behavior for non-
Win32 subsystems when installing the base utilities (which installs
the Interix subsystem) or Server for NFS. If you enable case
sensitivity and then subsequently uninstall Server for NFS and the
base utilities, Windows Services for UNIX Setup will restore the
default, case-insensitive behavior of non-Win32 subsystems.
