{"id":46,"date":"2009-06-04T13:26:25","date_gmt":"2009-06-04T19:26:25","guid":{"rendered":"https:\/\/www.chrisedwards.dreamhosters.com\/blog\/2009\/06\/04\/why-does-iis-fail-when-i-reference-a-net-35-assembly-in-aspnet\/"},"modified":"2011-08-21T15:11:02","modified_gmt":"2011-08-21T21:11:02","slug":"why-does-iis-fail-when-i-reference-a-net-35-assembly-in-aspnet","status":"publish","type":"post","link":"http:\/\/architester.com\/blog\/2009\/06\/04\/why-does-iis-fail-when-i-reference-a-net-35-assembly-in-aspnet\/","title":{"rendered":"Why does IIS fail when I reference a .NET 3.5 assembly in ASP.NET?"},"content":{"rendered":"<p>I added a reference to a .NET 3.5 assembly in one of our ASP.NET web pages. Visual studio warned me that the website project was using .NET 2.0 and needed to be upgraded to use 3.5. So I right clicked on the web project, changed it to use 3.5, and added my reference. All was well with the world\u00e2\u20ac\u00a6<\/p>\n<p>\u00e2\u20ac\u00a6That is until I hear the clear \u00e2\u20ac\u0153DOH!!!\u00e2\u20ac\u009d from my CCTray app, and the dreaded \u00e2\u20ac\u0153Red \u00e2\u20ac\u02dcC\u00e2\u20ac\u2122\u00e2\u20ac\u009d icon, indicating that I just broke the build.&#160; \u00e2\u20ac\u0153Doh!!!\u00e2\u20ac\u009d indeed!<\/p>\n<p>This perplexed me for a while until I realized that our app does not deploy a web.config file. However, the web.config file contains the setting telling IIS what compiler (2.0, 3.5) to use. Once I realized this, I created a web.config, committed it to svn, and got the familiar \u00e2\u20ac\u0153Whoohoo!\u00e2\u20ac\u009d sound from CCTray along with the nice \u00e2\u20ac\u0153Green \u00e2\u20ac\u02dcC\u00e2\u20ac\u2122\u00e2\u20ac\u009d. All is once again well with the world!<\/p>\n<p>For more information on this issue, check out:    <br \/><a href=\"http:\/\/blogs.msdn.com\/webtopics\/archive\/2009\/01\/30\/where-is-asp-net-3-5-on-iis.aspx\">http:\/\/blogs.msdn.com\/webtopics\/archive\/2009\/01\/30\/where-is-asp-net-3-5-on-iis.aspx<\/a><\/p>\n<p>-=CE=-<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I added a reference to a .NET 3.5 assembly in one of our ASP.NET web pages. Visual studio warned me that the website project was using .NET 2.0 and needed to be upgraded to use 3.5. So I right clicked on the web project, changed it to use 3.5, and added my reference. All was [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13,12],"tags":[14,69,70],"class_list":["post-46","post","type-post","status-publish","format-standard","hentry","category-aspnet","category-iis","tag-net-35","tag-aspnet","tag-iis"],"aioseo_notices":[],"aioseo_head":"\n\t\t<!-- All in One SEO 5.0.1 - aioseo.com -->\n\t<meta name=\"robots\" content=\"max-image-preview:large\" \/>\n\t<meta name=\"author\" content=\"ChrisEdwards\"\/>\n\t<link rel=\"canonical\" href=\"http:\/\/architester.com\/blog\/2009\/06\/04\/why-does-iis-fail-when-i-reference-a-net-35-assembly-in-aspnet\/\" \/>\n\t<meta name=\"generator\" content=\"All in One SEO (AIOSEO) 5.0.1\" \/>\n\t\t<meta property=\"og:locale\" content=\"en_US\" \/>\n\t\t<meta property=\"og:site_name\" content=\"Architester - Chris Edwards | Design, Testing &amp; Architecture\" \/>\n\t\t<meta property=\"og:type\" content=\"article\" \/>\n\t\t<meta property=\"og:title\" content=\"Why does IIS fail when I reference a .NET 3.5 assembly in ASP.NET? 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