安装完毕之后，新建一个工程，发现如题所示的error，version有问题。在网上查了下，很多人都有碰到，但是都没有写明如何解决，其实，解决方法在Qt Creator的帮助文件里就有提到了：
Term Meaning
Auto-detected Qt The version of Qt installed on your system. This is the Qt version for theqmake command found in your PATH.
Default Qt The version of Qt configured in Tools -> Options -> Qt 4 -> Default Qt Version. This is the Qt version used by your new projects. It defaults to Auto-detected Qt.
Project Qt The version of Qt configured in Build&Run -> Build Settings -> Build Configurations. This is the Qt version that is actually used by a particular project. It defaults to Default Qt.
Shadow Build Shadow building means building a project in a separate directory, the build directory. The build directory is different from the source directory. One of the benefits of shadow building is that it keeps your source directory clean. Shadow building is the best practice if you need many build configurations for a single set of source.
设置Default Qt变量为你Qt Creator的安装路径，入C:\Qt\2009.01 就OK了，再次运行之后，Qt会自动找到Creator的version，并设置Qt 4.5.0 (open source)变量。
That is all。
