Mixed mode assembly is built against version 'v2.0.50727' of the runtime and cannot be loaded in the 4.0 runtime without additio

 

最近在升级到VS2010后，程序出现了如下这条错误：

Mixed mode assembly is built against version 'v2.0.50727' of the runtime and cannot be loaded in the 4.0 runtime without additional configuration information.

 

经过网上查找，最后在CONFIG 中添加如下代码解决，这个文件为appname.exe.config：

 

 

<CONFIGURATION>

    <STARTUP useLegacyV2RuntimeActivationPolicy="true">

         <SUPPORTEDRUNTIME version="v4.0" />

         <REQUIREDRUNTIME version="v4.0.20506" />

    </STARTUP>

</CONFIGURATION>

  

原文地址：http://social.msdn.microsoft.com/Forums/en/clr/thread/58271e39-beca-49ac-90f9-e116fa3dd3c0

注意：VS2010 默认也会根据项目添加 STARTUP这个节点，但是仍然会报错。

需要手动添加如下代码，问题才得以解决：

useLegacyV2RuntimeActivationPolicy="true"

<REQUIREDRUNTIME version="v4.0.20506" />