The entries in the FileSystem subkey specify the behavior of NTFS and FAT, respectively, under the following Registry path:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\FileSystem
NtfsDisable8dot3NameCreation REG_DWORD 0 or 1
Controls whether NTFS will create a short name for a filename that is not in the format xxxxxxxx.yyy, contains extended characers, or both. Creating short names impacts performance, so some sites may want to set this value to 1 (true) if they do not intend to either use DOS applications on long names, or share disks with different code page machines (i.e., machines in the U.S.). For example, in the Far East, where all native file names generate short names, set this value to 1.
You must reboot the system for a change to this value to take effect.
Default: 0 (false)
Win31FileSystem REG_DWORD 0 or 1
Controls whether the FAT will allow creation, enumeration, opening, or querying of long file names, and whether extended time stamp information (CreationTime and LastAccessTime) is stored and reported. Set this value to 1 (true) to revert to basic Win3x (and WindowsNT 3.5) semantics.
Note
Changing this value does not change any disk structures. It simply changes how the system behaves from now on.
You must reboot the system for a change to this value to take effect.
Default: 0 (false)