DOCUMENT:Q231790 16-MAY-2002 [winnt] TITLE :File Sharing Operations to a Share on Local Computer May Be Slow PRODUCT :Microsoft Windows NT PROD/VER::4.0 OPER/SYS: KEYWORDS:kbWinNT4sp6fix ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server version 4.0, Terminal Server Edition - Microsoft Windows NT Workstation version 4.0 - Microsoft Windows NT Server version 4.0 ------------------------------------------------------------------------------- SYMPTOMS ======== When you share files on a computer, and then connect to that sharepoint from the same computer, file operations such as XCOPY may be slow if TCP/IP is the protocol being used. CAUSE ===== If for example you share out a directory named "test", and then connect to that share from the same computer it was shared from, the TCP/IP stack uses what is called the "loopback" interface. The use of the "loopback" interface is to prevent packets between the client and server (which are on the same computer) from actually being sent out on the network cable. TCP/IP implements "nagling" and "delayed acknowledgment", even though the interface in this case is loopback. This can cause unnecessary delays. More details on nagling are available in ftp://ftp.microsoft.com/bussys/winnt/winnt-docs/papers/Tcpimp2.exe RESOLUTION ========== Windows NT Server or Workstation 4.0 ------------------------------------ To resolve this problem, obtain the latest service pack for Windows NT 4.0 or the individual software update. For information on obtaining the latest service pack, please go to: - http://www.microsoft.com/Windows/ServicePacks/ -or- - Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack For information on obtaining the individual software update, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web: http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS Windows NT Server 4.0, Terminal Server Edition ---------------------------------------------- To resolve this problem, obtain the latest service pack for Windows NT Server 4.0, Terminal Server Edition. For additional information, please see the following article in the Microsoft Knowledge Base: Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack STATUS ====== Microsoft has confirmed this to be a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Windows NT Server version 4.0, Terminal Server Edition Service Pack 6. Additional query words: 4.00 ====================================================================== Keywords : kbWinNT4sp6fix Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbNTTermServ400 kbNTTermServSearch Version : :4.0 Hardware : ALPHA x86 Issue type : kbbug Solution Type : kbfix ============================================================================= 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 2002.