No such file directory. QApplication. How to link the library?

Question

Qt

Good afternoon.
Installed Qt Creator 3.3.1 and Qt 5.4...
So at first, everything started well. At one point, I decided to run from a folder, and not through a shortcut. And... Now Qt Creator started to write that it does not find the QApplication directory and a number of others... All compilers, debuggers and kits are connected correctly. Maybe somewhere you need to manually enter the path? Tell me please.
Thanks in advance :)

Answer 1

And... Now Qt Creator started to write that it does not find the QApplication directory and a number of others..

It's not clear if he writes this at startup or when you compile something in it or when you try to run the compiled program?