title: How do I build boost with Visual Studio 2008 when I have multiple Visual Studio versions installed?
body: <p>I know how to build boost with the latest visual studio on my machine (<a href="https://stackoverflow.com/questions/3977555/build-boost-library">this question, for example</a>)</p>
  
  <p>However, I need to build the libs for Visual Studio 2008 (vc9)</p>
  
  <p>I tried using toolset=vc9 but I get problems/no success.</p>
  
  <p>How can I build the libs for vc9?</p>
  
  <p>After I run boostrap I try running</p>
  
  <pre><code>b2 toolset=vc9
  </code></pre>
  
  <p>but the output is:</p>
  
  <blockquote>
    <p>C:/Development/boost
    50/boost_1_50_0/boost_1_50_0/tools/build/v2/build\toolset.jam:39: in
    toolset.using rule vc9.init unknown in module toolset</p>
    
    <p>C:/Development/boost
    50/boost_1_50_0/boost_1_50_0/tools/build/v2\build-system.jam:481: in
    process-explicit-toolset-requests</p>
    
    <p>C:/Development/boost
    50/boost_1_50_0/boost_1_50_0/tools/build/v2\build-system.jam:562: in
    load</p>
    
    <p>C:\Development\boost
    50\boost_1_50_0\boost_1_50_0\tools\build\v2/kernel\modules.jam:283: in
    import</p>
    
    <p>C:\Development\boost
    50\boost_1_50_0\boost_1_50_0\tools\build\v2/kernel/bootstrap.jam:142:
    in boost-build</p>
    
    <p>C:\Development\boost 50\boost_1_50_0\boost_1_50_0\boost-build.jam:17:
    in module scope</p>
  </blockquote>