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QT Designer 5.3+ crashes when clicking inside the widget toolbox

  • Hello,

    I have a new developpement station that I'm setting up. I install the usual tools (Visual Studio, Vs-Addin, Qt libs etc.) Everything fits with my current computer (same os, Win7 Pro, 64 bit, 32gb ram, libs are installed in the same places).

    I have the weirdest of bug with Qt Designer. Whether I lunch it from inside VS2012 or straight from the /bin directory. It opens up fine, I can open existing ui files, edit properties, etc. But if I click on any widget to drag one, it crashes. I've tried

    Qt 5.3.1 (internal build)
    Qt 5.3.2 (build made by Tver-Soft)
    Qt 5.5.0 (build found on

    They all crash as soon as I click in the widget toolbox. Funny thing, if I compile my application (with 5.3.2) it compiles just fine and runs without any problem. The problem only seem related to the Designer itself. It has no plugins installed in any of the versions. Simple vanila Qt.

    Funny enough, I tried Qt 4.7.4 (internal build) and it worked fine. I can edit documents add widgets, etc.

    My feeling thus far is it might be OpenGL/DirectX. This station has a simple on-board video card (Intel HD 4600) while other dev station have an NVidia Geforce GT something... But it seems far fetched.

    Crash report gives nothing interesting. Seems to come from ntdll.

    If anyone has a good idea, I'm willing to try it. Thanks alot!


  • Lifetime Qt Champion

    Hi and welcome to devnet,

    Do you mean that the nVidia powered station don't suffer from that but your with the Intel card does ?

  • Sorry for the long time to reply. But we found the problem and I figure this might help some people. It was not related to the video driver at all.

    It was Dell Backup software. Apparently they are also Qt5 but install of distributing the dll alongside their application, they register the 32-bit DLL of Qt in the Windows registry. I was not aware, but this apparently preceeds the PATH lookup and even though our DLL where in the same directory as Qt Designer, it was loaded by Designer (x64 version) and would result in a crash.

    I since found similar issue:

    Now I'm sort of wondering if there would have been a way to prevent this from happening. Maybe change the DLLs name to a qtModuleName_CompleteVersion_Compiler_platform.dll scheme (like Qt5Core.dll becomes QtCore_5_4_1_MSVC110_x64.dll). We have some library on a similar model (GenICam).

  • Lifetime Qt Champion

    That's one situation that I haven't' see yet…

    AFAIK, you should be able to achieve that using the -qtlibinfix when building Qt yourself

    Thanks for sharing your finding !

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