Introduction In the world of system administration and legacy hardware maintenance, creating bootable USB drives is often essential for recovery, diagnostics, or password reset tasks. Three terms frequently surface in this context: CLNPWD , HP USB Disk Storage Format Tool , and boot files . This write-up explains each component and how they relate to creating a bootable USB drive capable of resetting Windows local administrator passwords using the Offline NT Password & Registry Editor (commonly known as clnpwd or chntpw ). 1. CLNPWD – Offline NT Password & Registry Editor CLNPWD (often a misspelling or shorthand for chntpw – “Change NT Password”) is a well-known open-source utility used to reset or blank local Windows account passwords by directly editing the SAM (Security Account Manager) registry hive offline. It works on Windows NT-based systems (NT, 2000, XP, Vista, 7, 8, 10, and some server versions).