DOCUMENT:Q275020 08-MAY-2002 [winnt] TITLE :SMB Signing May Become Unsynchronized PRODUCT :Microsoft Windows NT PROD/VER::4.0,4.0 SP4,4.0 SP5,4.0 SP6,4.0 SP6a OPER/SYS: KEYWORDS:kbWinNT400PreSP7Fix ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Workstation versions 4.0, 4.0 SP4, 4.0 SP5, 4.0 SP6, 4.0 SP6a - Microsoft Windows NT Server versions 4.0, 4.0 SP4, 4.0 SP5, 4.0 SP6, 4.0 SP6a ------------------------------------------------------------------------------- SYMPTOMS ======== When a session is established from a workstation to a server, and server message block (SMB) signing is enabled, the signatures may become out of synchronization and cause all subsequent requests that are sent by the workstation to be rejected by the server. This is more likely to occur if the workstation and server are separated by a slow WAN link. CAUSE ===== This behavior occurs only if there is an active SMB session established to the same server to which the workstation is trying to connect. If the workstation sends an SMB from the other session while the SMB session setup for the new session is outstanding, the signature count on the server may become out of synchronization with the signature count on the workstation. This results in all subsequent SMB commands that are sent to the server being rejected. All responses after this point are returned to the workstation with a status of "ACCESS_DENIED." 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. To resolve this problem, contact Microsoft Product Support Services to obtain the fix. 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 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. The English version of this fix should have the following file attributes or later: Date Time Version Size File name Platform ------------------------------------------------------------------ 03/01/2001 11:12pm 4.0.1381.7086 266,224 Rdr.sys Intel To resolve this problem, obtain the individual package referenced earlier, or obtain the Windows NT 4.0 Security Rollup Package. For additional information about the Security Rollup Package, click the article number below to view the article in the Microsoft Knowledge Base: Q299444 Post-Windows NT 4.0 Service Pack 6a Security Rollup Package (SRP) STATUS ====== Microsoft has confirmed this to be a problem in the Microsoft products that are listed at the beginning of this article. Additional query words: ====================================================================== Keywords : kbWinNT400PreSP7Fix Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTW400sp5 kbWinNTW400sp4 kbWinNTSsearch kbWinNTS400sp6 kbWinNTS400sp5 kbWinNTS400sp4 kbWinNTS400search kbWinNTS400 kbWinNTW400sp6 kbWinNTW400SP6a Version : :4.0,4.0 SP4,4.0 SP5,4.0 SP6,4.0 SP6a 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.