JSI Tip 6841. How do I change the behavior of Windows XP so it allows case-sensitivity for Interix and SFU?

If you use Services For Unix 2.2 or 3.0, you may find that you cannot use names like JSI.TXT, JSI.txt, and jsi.txt in the same folder.

Windows NT-based computers are case-preserving but NOT case-sensitive.

To support SFU, Windows XP allows you to change the default behavior for non-Win32 sub-systems.

NOTE: If you turn on case-sensitivity and subsequently remove SFU, the uninstall restores the case-insensitive behavior of non-Win32 sub-systems.

After installing one of these sub-systems, you can turn on case-sensitivity:

1. Copy / Paste the following to a SFU_Case.reg file:


\[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\kernel\]

2. Merge the SFU_Case.reg file with your registry, or run regedit /s SFU_Case.reg.

3. Shutdown and restart Windows XP.

Hide comments


  • Allowed HTML tags: <em> <strong> <blockquote> <br> <p>

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.