Unsolved Qt: can't build- qmake error 3

[kr.barth]

Hey!

this is my first project using qt and i'm having trouble compiling. I'm using qt 5.11.1 MinGw 32bit and when trying to build get the following error message:

ASSERT: "fileName.isEmpty() || isAbsolutePath(fileName)" in file C:/Users/qt/work/qt/qtbase/qmake/library/ioutils.cpp, line 53

This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.
10:37:58: Der Prozess "D:\Qt\5.11.1\mingw53_32\bin\qmake.exe" wurde mit dem Rückgabewert 3 beendet.
Fehler beim Erstellen/Deployment des Projekts simpleDataWindow (Kit: Desktop Qt 5.11.1 MinGW 32bit)
Bei der Ausführung von Schritt "qmake"

I can compile the qt examples without any issues.

does anyone have a idea on how to fix this? would appreciate any help!

[jsulm]

@kr.barth Hi and welcome!
Can you show your pro file? Also, did you try to delete the build folder and run qmake again?