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QT 5.6 app works on win 7, 8, &10 but not Vista - why?

  • All is well on Windows 7, 8 and 10

    On Windows Vista we have users on "OS Version: 6.0.6002 Service Pack 2 Build 6002" who are getting the following error:

    cannot find or load the Qt platform plugin"windows"
    Available plugins are: Windows.
    Reinstalling the application may fix this problem.

    Our test setup has the error if we do not have Service Pack 2 installed. However users in the wild ARE STILL having the issue on Service Pack 2.

    We have seen posts like these to fix the problem. However its odd that only some windows Vista SP2 users are experiencing the issue.

    Has anyone else experienced this problem or know why this may be?

    Thank you kindly,

    Our qt.conf in the application basedir
    Plugins = QtPlugins
    Translations = QtPlugins/translations


  • Moderators

    Hi, welcome to devnet

    The plugin is found so the problem is it can't load. Often the reason a particular library does not load is that some dependencies are not met. A usual suspect are the compiler runtime libraries. Those are installed by a lot of apps out there so it's possible that a lot of users have them but some don't.

    Which compiler do you use? Do you distribute runtime libs?
    To make sure you can run that qwindows.dll through Dependency Walker on the problematic machine to see what's missing.

  • Thank you for the reply.

    After the user went to Windows Update and installed "additional packages" his problem went away.

    VS 2013 compiler.

    We distribute:

    I will have the next person with the issue try to run the Dependency Walker.

    Thank you!


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