title: Office 2010 addin - VSTO version confusion
body: <p>I am struggling with creating a Word 2010 addin and creating a windows installer package to deploy the addin. The target framework for the addin is .NET 3.5.</p>
  
  <p>From what I understand when reading the deployment guide from Microsoft, VSTO runtime for .NET 3.5 is installed with Office 2010.<br>
  Does this mean I can assume that as long as Word 2010 is installed on the target computer, the VSTO runtime for .NET 3.5 will be present as well?<br>
  <a href="http://msdn.microsoft.com/en-us/library/ff937654.aspx" rel="nofollow">http://msdn.microsoft.com/en-us/library/ff937654.aspx</a></p>
  
  <p>Another problem I am having concerns which version of the vsto I should reference.<br>
  The deployment example code available via the link above references an assembly which I assume (version is 9, not 4 that I was expecting) is part of the VSTO 2010 targeted for .NET 3.5<br>
  <code>Program Files\Reference Assemblies\Microsoft\VSTO\v9.0\ Microsoft.Office.Tools.v9.0.dll </code> </p>
  
  <p>But when I check the launch conditions for the installer in the example, it searches for VSTO 2010 Runtime by checking for the version string in the key<br>
  <code>HKLM\Software\Microsoft\VSTO Runtime Setup\V4R</code><br>
  or<br>
  <code>HKLM\Software\Microsoft\VSTO Runtime Setup\V4</code></p>
  
  <p>However the assemblies referenced had v9.0 in the folder path which makes me think they would match<br>
  <code>HKLM\Software\Microsoft\VSTO Runtime Setup\V9.0.21022 or V9.0.30729</code>  </p>
  
  <p>Can I still use v4 even though when I reference the assembly I use v9, or am I mixing things up here?</p>