During Qt Creator Compilation: cannot open file & #39; debug \ QtGuiEx.exe & am

During Qt Creator Compilation: cannot open file 'debug \. exe 'File not found

When you use Qt Creator to compile a project, the error shown in the question appears. The red part is the project name.

In the Build column of Qt Creator, click clean all and clean project "QtGuiEx", and then compile the program. This error still occurs.

In the project directory, you can find qtguiex.exe In the debug folder.

Why can't I open this file? Suddenly, we found that the ui window (or interface) generated during the last debug (OR run) has not been closed.

After the ui window (or interface) is closed and then built, this error is no longer displayed and can be compiled properly.