如果应用程序是针对 3.5 构建的，那么您将无法在不安装 3.5 的情况下运行您的应用程序.同时安装 4.0 和 3.5 没有问题 - 这是一个非常常见的场景.

You won't be able to run your application without installing 3.5 if that is what the application is built against. There is no problem in having both 4.0 and 3.5 installed at the same time - this is a very common scenario.

要解决您的问题，请安装 .NET Framework 3.5.

To solve your problem install .NET Framework 3.5.