http://msmvps.com/blogs/carlosq/archive/2009/03/24/the-strange-case-of-lt-unknown-error-gt-8013150a-loading-a-visual-studio-add-in.aspxVisual Studio add-ins are not very friendly when trying to auto-update them (at least as of Visual Studio 2008), so when deploying an add-in for internal use within an organization, one creative idea is to put the assembly dll in a shared network folderenCommunityServer 2008.5 SP2 (Build: 40407.4157)http://msmvps.com/blogs/carlosq/archive/2009/03/24/the-strange-case-of-lt-unknown-error-gt-8013150a-loading-a-visual-studio-add-in.aspx#1697097Mon, 29 Jun 2009 12:39:22 GMTd67277c4-116b-43f1-b688-e9ef184ea916:1697097Carlos Quintero (Microsoft MVP) blog<p>From time to time I blog about strange cases of errors when loading add-ins for Visual Studio. At least</p> <img src="http://msmvps.com/aggbug.aspx?PostID=1697097" width="1" height="1">