DOCUMENT:Q164351 09-AUG-2001 [winnt] TITLE :Command Prompt's Treatment of Long File Extensions PRODUCT :Microsoft Windows NT PROD/VER:winnt:4.0 OPER/SYS: KEYWORDS:kbusage ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Workstation version 4.0 - Microsoft Windows NT Server version 4.0 ------------------------------------------------------------------------------- IMPORTANT: This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore it if a problem occurs. For information about how to do this, view the "Restoring the Registry" Help topic in Regedit.exe or the "Restoring a Registry Key" Help topic in Regedt32.exe. SYMPTOMS ======== When you perform file management using wildcards from the command prompt, files with long extensions may be unexpectedly displayed, copied, or deleted. CAUSE ===== By default, Windows NT 4.0 mimics the Windows 95 behavior of truncating long file extensions under certain operations from the command line. File management operations directed at a 3 digit extension may also include files with an extension containing more than 3 digits where the first 3 digits match the operation argument. This behavior only affects file management commands such as dir, del, move, and copy that are executed at a command prompt. File management operations performed by Find, File Manager, or Windows NT Explorer do not perform in this manner. RESOLUTION ========== WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. For information about how to edit the registry, view the "Changing Keys And Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it. To control this behavior, perform the following steps: 1. Start Registry Editor (Regedt32.exe) and go to the following subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\FileSystem 2. Edit the following value: Win95TruncatedExtensions : REG_DWORD : 0/1 [Default=1] The following is an example showing the behavior with each setting on a directory containing the two files: - htm - html Default behavior of Win95TruncatedExtensions set to 1: DEL *.htm - Deletes both 1.htm and 2.html. DEL *.html - Deletes 2.html. Modified behavior of Win95TruncatedExtensions set to 0. DEL *.htm - Deletes 1.htm DEL *.html - Deletes 2.html 3. For the changes to take effect, restart your computer. Additional query words: remove fat ntfs subdir ====================================================================== Keywords : kbusage Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400 Version : winnt:4.0 Issue type : kbprb ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.