DOCUMENT:Q216795 08-MAY-2002 [winnt] TITLE :Semaphore Error After Disabling Write Behind Caching PRODUCT :Microsoft Windows NT PROD/VER:winnt:4.0 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server version 4.0, Terminal Server Edition ------------------------------------------------------------------------------- SYMPTOMS ======== When you change the following registry subkey HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Rdr\Parameters Value Name: UseWriteBehind Data Type: REG_DWORD Data: 0 on a computer running Microsoft Terminal Server and then try to copy a file to a remote share over the network, the following error message is displayed: To Many Posts Were Made to a Semaphore. This may occur when you run the Terminal Server console and when a client is connected to a Terminal Server Session, because both are copying files from the Terminal Server computer to a remote share. CAUSE ===== This problem occurs because of a problem in the redirector, which manipulates an operating system semaphore. WORKAROUND To work around this problem: - Re-enable write behind caching by setting UseWriteBehind to 1. -or- - Apply the hotfix mentioned below. RESOLUTION ========== A supported fix is now available from Microsoft, but it is only intended to correct the problem described in this article and should be applied only to systems experiencing this specific problem. This fix may receive additional testing at a later time, to further ensure product quality. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next that contains this fix. To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, please go to the following address on the World Wide Web: http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS NOTE: In special cases, charges that are normally incurred for support calls may be canceled, if a Microsoft Support Professional determines that a specific update will resolve your problem. Normal support costs will apply to additional support questions and issues that do not qualify for the specific update in question. Date Time Version Size File name Platform ---------------------------------------------------------------- 02/14/99 11:10:00 PM 4.0 264,848 Rdr.sys Intel 02/14/99 11:09:50 PM 4.0 506,928 Rdr.sys Alpha (http://support.microsoft.com/download/support/mslfiles/) Install the latest service pack for Windows NT server 4.0, Terminal Server Edition. Service pack 4 for Windows Terminal Server contains the fix for this bug. STATUS ====== Microsoft has confirmed this to be a problem in Windows NT 4.0 Terminal Server version SP4. This problem has been corrected in the latest U.S. service pack for Windows NT 4.0 Terminal Server version SP4. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces): S E R V P A C K Additional query words: Terminalsvr Semaphore ====================================================================== Keywords : Technology : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbNTTermServ400 kbNTTermServSearch Version : winnt:4.0 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.