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QWT plugin into QT Designer specified module could not be found

  • I am trying to use QWT plugin within QT Designer. I followed all the doc steps, I compiled the plugin and modified the PATHs as follows:


    However, when I launch QT Creator, the plugin could not be loaded correctly. I get the message:

    Can not load library .... The specified module could not be found.
    I don't see where the problem can be.

    Any help will be more than appreciated.

  • Lifetime Qt Champion

    Hi and welcome to the forums
    You compiled it with same compiler as Creator and in Release mode ?
    alt text

  • @mrjj thank you for your answer.

    I used the same compiler (MSVC2015) as the one used to compile as shown in the pic.

    The config file in windows says that both debug & release modes are compiled. Should I changed it to the release only ?

    win32 {
        # On Windows you can't mix release and debug libraries.
        # The designer is built in release mode. If you like to use it
        # you need a release version. For your own application development you
        # might need a debug version. 
        # Enable debug_and_release + build_all if you want to build both.
        CONFIG           += debug_and_release
        CONFIG           += build_all

  • Lifetime Qt Champion

    @DSpider Did you use same Qt version also?

  • @jsulm Not sure how to do this. Do I need to specify it in the ?

    I have now another problem when trying to compile with nmake.

    ......\Qt\5.11.2\msvc2015\include\QtCore\qglobal.h(45): fatal error C1083: can not open file include : 'type_traits' : No such file or directory

    I saw that I should specify in the .build file to use c++11 which I did, the problem persists.

    Can this be related to the Qt version ?

    Best regards

  • I finally managed to compile it.
    Just by executing VsVars32.bat before compilation, this is supposed to load environment variables. I followed this answer.

    Thank you all for your help.

  • @DSpider great! please don't forget to mark your post as solved. Thanks.