This came up during my last quest. Can someone please explain why qmake sets its installation path statically at the compile time. This make it impossible to change the name of the installing folder after installing.
Does this should be reported as a bug or is there a reason for this?
I'm not sure if this is your case but might as well be:
If you rename the installation folder of Qt, you have to adjust the "QTDIR" environment variable and update the "PATH" environment variable.
(on Windows: Press [Win]+[Pause] => Advanced => Environment Variables)