{"id":1028,"date":"2010-10-14T15:25:34","date_gmt":"2010-10-14T14:25:34","guid":{"rendered":"http:\/\/mccltd.net\/blog\/?p=1028"},"modified":"2010-11-22T17:11:53","modified_gmt":"2010-11-22T17:11:53","slug":"disabling-smb-v2-0-on-windows-vista-win7-server-2008","status":"publish","type":"post","link":"http:\/\/darenmatthews.com\/blog\/?p=1028","title":{"rendered":"Disabling SMB v2.0 on Windows Vista \/ Win7 \/ Server 2008"},"content":{"rendered":"<div>\n<p>Server Message Block (SMB) Protocol\u00a0 is the file sharing protocol  used by default on Windows-based computers. SMB 1.0 was designed for  early Windows network operating systems such as Microsoft LAN Manager  and Windows for Workgroups, but until Windows Server 2008 and Vista, all  Microsoft-based operating systems continued to use it more or less in  its original format.<\/p>\n<p>SMB 2.0 was introduced in Windows Vista and Windows Server 2008. SMB  2.0 is designed for the needs of the next generation of file servers.  Windows Server 2008 and Windows Vista support both SMB 1.0 and SMB 2.0  in order to preserve backward compatibility.<!--more--><\/p>\n<p>Some of the enhancements in SMB 2.0, include:<\/p>\n<ul>\n<li>Sending multiple SMB commands in the same packet which reduces the number of packets sent between a client and server<\/li>\n<li>Larger buffer sizes<\/li>\n<li>Increased scalability, including an increase in the number of  concurrent open file handles on the server and the number of shares that  a server can share out<\/li>\n<li>Support for Durable Handles that can withstand short network problems<\/li>\n<li>Support of Symbolic Links<\/li>\n<\/ul>\n<p>Testing done with copying large files between Windows Vista and  Windows Server 2008, and then Vista to Windows 2003, have shown that by  using SMB 2.0 the file copying was, in averege, 2 times faster than with  older operating systems.<\/p>\n<p>However, while SMB 2.0 seems to do a good job if BOTH client and  server OSs support it, in some cases it will slow things down. The reson  for this is that the version of SMB used for file sharing is determined  during the SMB session negotiation. If both the client and server  support SMB 2.0, then SMB 2.0 is selected during the initial  negotiation. However, if they don&#8217;t both support it, SMB 1.0 will be  used to in order to preserve backwards compatibility.<\/p>\n<p>The SMB protocol version to be used for file operations is decided  during the negotiation phase. During the negotiation phase, a Windows  Vista client advertises to the server that it can understand the new SMB  2.0 protocol. If the server (Windows Server 2008 or otherwise)  understands SMB 2.0, then SMB 2.0 is chosen for subsequent  communication. Otherwise the client and server use SMB 1.0.<\/p>\n<p>When using the terms &#8220;client&#8221; and &#8220;server&#8221; in case of file and print  sharing, it does not necessarily mean that a client-type OS such as  Vista &#8220;always&#8221; connects to a server-type Os such as Windows Server 2008.  Sometimes, a Vista computer will connect to another Vista computer, and  in that case, the computer that is &#8220;serving&#8221; the shares is considered  to be the &#8220;server&#8221;.<\/p>\n<p>Here&#8217;s how SMB is used when related to SMB versions:<\/p>\n<ul>\n<li>When a Windows Server 2008\/Vista &#8220;client&#8221; connects to a Windows Server 2008\/Vista &#8220;server&#8221;, SMB 2.0 is used.<\/li>\n<li>When a Windows Server 2008\/Vista &#8220;client&#8221; connects to a Windows 2000\/XP\/2003 &#8220;server&#8221;, SMB 1.0 is used.<\/li>\n<li>When a Windows 2000\/XP\/2003 &#8220;client&#8221; connects to a Windows Server 2008\/Vista &#8220;server&#8221;, SMB 1.0 is used.<\/li>\n<li>When a Windows 2000\/XP\/2003 &#8220;client&#8221; connects to a Windows 2000\/XP\/2003 &#8220;server&#8221;, SMB 1.0 is used.<\/li>\n<\/ul>\n<p>So, for troubleshooting purposes, mostly in an environment that has  mixes operating systems, you might want to consider disabling SMB 2.0.  You need to do so on both the &#8220;client&#8221; and the &#8220;server&#8221; operating  systems.\u00a0To disable SMB 2.0 for Windows Vista or Windows Server 2008  systems that are the \u201cclient\u201d systems run the following commands:<\/p>\n<pre>sc config lanmanworkstation depend= bowser\/mrxsmb10\/nsi\r\nsc config mrxsmb20 start= disabled<\/pre>\n<p>Note there&#8217;s an extra &#8221; &#8221; (space) after the &#8220;=&#8221; sign.<\/p>\n<p>To enable back SMB 2.0 for Windows Vista or Windows Server 2008  systems that are the \u201cclient\u201d systems run the following commands:<\/p>\n<pre>sc config lanmanworkstation depend= bowser\/mrxsmb10\/mrxsmb20\/nsi\r\nsc config mrxsmb20 start= auto<\/pre>\n<p>Again, note there&#8217;s an extra &#8221; &#8221; (space) after the &#8220;=&#8221; sign.<\/p>\n<p>In order to disable SMB 2.0 on the server-side computer, follow these steps:<\/p>\n<h2>Warning!<\/h2>\n<p>This document contains instructions for editing the registry. If you  make any error while editing the registry, you can potentially cause  Windows to fail or be unable to boot, requiring you to reinstall  Windows. Edit the registry at your own risk. Always back up the registry  before making any changes. If you do not feel comfortable editing the  registry, do not attempt these instructions. Instead, seek the help of a  trained computer specialist.<\/p>\n<ol>\n<li>Run &#8220;regedit&#8221; on Windows Server 2008 based computer.<\/li>\n<li>Expand and locate the sub tree as follows.\n<pre>HKLM\\System\\CurrentControlSet\\Services\\LanmanServer\\Parameters<\/pre>\n<\/li>\n<li>Add a new REG_DWORD key with the name of &#8220;Smb2&#8221; (without quotation mark)\n<pre>Value name: Smb2\r\nValue type: REG_DWORD\r\n0 = disabled\r\n1 = enabled<\/pre>\n<\/li>\n<li>Set the value to 0 to disable SMB 2.0, or set it to 1 to re-enable SMB 2.0.<\/li>\n<li>Reboot the server<\/li>\n<\/ol>\n<\/div>\n<div>&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8211;<\/div>\n<div>Courtesy:\u00a0Petri IT Knowledgebase at <a href=\"http:\/\/www.petri.co.il\/how-to-disable-smb-2-on-windows-vista-or-server-2008.htm\">http:\/\/www.petri.co.il\/how-to-disable-smb-2-on-windows-vista-or-server-2008.htm<\/a><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Server Message Block (SMB) Protocol\u00a0 is the file sharing protocol used by default on Windows-based computers. SMB 1.0 was designed for early Windows network operating systems such as Microsoft LAN Manager and Windows for Workgroups, but until Windows Server 2008 and Vista, all Microsoft-based operating systems continued to use it more or less in its [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[27,13],"tags":[49,47],"_links":{"self":[{"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1028"}],"collection":[{"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1028"}],"version-history":[{"count":4,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1028\/revisions"}],"predecessor-version":[{"id":1090,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1028\/revisions\/1090"}],"wp:attachment":[{"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1028"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1028"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1028"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}