我有以下MSDN链接：
.NET Framework Versions and Dependencies
Each new version of the .NET Framework retains features from the prevIoUs versions and adds new features. The CLR is identified by its own version number. Some versions of the .NET Framework include a new version of the CLR,but others use an earlier version. For example,the .NET Framework 4 includes CLR 4,but the .NET Framework 3.5 includes CLR 2.0. (There was no version 3 of the CLR.) Although the .NET Framework 4.5 RC is an in-place update of the .NET Framework 4,the underlying CLR version number is 4.5.@H_301_8@
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文档还说，您只能在Windows XP Professional和Windows XP Home Edition上安装.NET Framework 4，.NET Framework 3.5 SP1，.NET Framework 2.0 SP2(即不提供4.5)。
我已经在其他地方读过.NET 4.5可以在Win XP上安装。所以这个文档就是指4.5RC(而不是最终的4.5框架)。
我的问题是，我们无法在XP机器上部署基于4.5的应用程序。微软会发布一个服务包吗？ (不太可能，因为他们不支持XP)
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