Im trying to add a header called 

#include <QPropertyAnimation>

but as soon as i add it into my project i get a ton of stray errors which are very unusual.

i can only stop the build process by press clean on the build.

iv read on stackoverflow that this issue can be resolved by retyping the code without using the systemcopy paste cache iv already tryied to retype the entire text. and im still trapped with this error. 

as soon as i uncomment the header i can successfuly build the project. 

the project has literly nothing in it except a push button without functionalyt witch is called push me and a mainwindow that has not been modified from creation.