http://blogs.msdn.com/b/vbteam/archive/2010/06/11/troubleshooting-errors-when-embedding-type-information-doug-rothaus.aspxVisual Studio 2010 has a new feature, Embed Interop Types , that can simplify application deployment and solve those pesky issues that can arise when using COM Interop and Primary Interop Assemblies (PIAs). If you&rsquo;ve ever had to ship multiple versionsen-USTelligent Evolution Platform Developer Build (Build: 5.6.50428.7875)http://blogs.msdn.com/b/vbteam/archive/2010/06/11/troubleshooting-errors-when-embedding-type-information-doug-rothaus.aspx#10322106Wed, 20 Jun 2012 08:45:33 GMT91d46819-8472-40ad-a661-2c78acb4018c:10322106Bob Marley<p>Yes this solves an issue, if by &#39;solve an issue&#39; you mean introduce an issue where there was none before. Yes, this is a typical Microsoft &#39;feature&#39; where your best bet is to undo what was done automatically without any kind of notification and change the new &#39;Embed Interop Types&#39; property back to &#39;false&#39; in your references to the PIA. Once you have done this the build issues you are experiencing will disappear and things will be as they were before this new &#39;feature&#39; was introduced. Great work Microsoft!</p> <div style="clear:both;"></div><img src="http://blogs.msdn.com/aggbug.aspx?PostID=10322106" width="1" height="1">