Problem in Qt application: mainwindow and buttons turn white

[A Former User]

Hi, i am new in Qt and i need some help.
I create a first program for test, a Qt Widget Application, following some tutorials on the internet. The program compiles but when i am using it, first the buttons and then the mainwindow turn white. They still functionaly, but the buttons and the mainwindow simple disappear.
I am using Windows 7 - 64 bits and installed Qt 5.5.1 (MSVC 2013, 32 bit).

[SGaist]

Hi and welcome to devnet,

Please post your code, without it it's pretty much Crystal Ball debugging.