installer path check error : an extra "i"

I tried to install the Qt 4.8.3 with MinGW, but it seems that the installer I downloaded here has some bug.

I installed MinGW 4.6 first (because I cannot find a suitable 4.4 version).

After that I tried to install Qt 4.8.3 MinGW, however, during the Qt installation, this message showed up :

There is a problem with your MinGW installation:
The installer could not find a valid C:\MinGW\iinclude\w32api.h (Only versions with W32API 3.13 are supported)

I notice that the path is not correct, an extra i is in “iinclude”.
This seems a bug in the installer….