Important: Please read the Qt Code of Conduct -

Cannot load library qwt_designer_plugin.dll is not a valid win32 application

  • Win7 x64
    Visual Studio 2013 x64
    Qt 5.5 x64
    I built qwt module for 64 bit Windows OS:
    I run "VS2013 x64 Native Tools Command Prompt"

    nmake install

    I copied qwt_designer_plugin.dll in C:/Qt/Qt5.5.1/Tools/QtCreator/bin/plugins/designer/
    and run Qt Creator

    Cannot load library C:/Qt/Qt5.5.1/Tools/QtCreator/bin/plugins/designer/qwt_designer_plugin.dll: %1 is not a valid win32 application

    In Qt Designer good load qwt_designer_plugin.dll module.

  • Lifetime Qt Champion

    If you Open Creator and look in Help->About Creator
    What version of visual studio is it compiled with?

  • @mrjj, hm "Qt Creator 3.5.1 Based on Qt 5.5.1 (MSVC 2013, 32 bit)
    whether there is a 64 bit version of Qt Creator for Windows?

    Qt Creator 3.5.1 for Windows (79 MB)    (info)
    Qt Creator 3.5.1 for Linux/X11 32-bit (103 MB)    (info)
    Qt Creator 3.5.1 for Linux/X11 64-bit (96 MB)    (info)
    Qt Creator 3.5.1 for Mac (84 MB)    (info)

  • Lifetime Qt Champion

    Dont think there is one.
    Im wondering if it will load 64 bit DLLS when its 32 app.
    (guessing its a no go)

  • Lifetime Qt Champion


    No there's no 64 bit pre-built QtCreator.

    And no again, a 32bit application can't load a 64 bit plugin/dll. You have to ensure that you use the same compiler and Qt version that were used to build QtCreator.

Log in to reply