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[Solved] Set environment variable for QT SDK (.dll file missing)

  • Hello all,

    I am a newb for QT , just downloaded the QT SDK for windows 7.
    It seems working fine when I debug any program from the IDE, but when I run any project exe (from release or debug folder) It shows message for so many .dll files are missing.

    I think I need to set some environment variables for it.
    I don't know what and how will I do it?
    If I am right then please let me know the settings for it. Or any other Ideas for the problem of .dll file missing.

    Thanks in advance


  • you can download the missing dll files and put it into qtsdk library directory.I think it may work.Ohterwise you can install latest version.

  • Moderators

    You are having problems running your code from the command line, is that correct?

    Check the run configuration creator uses (Projects->Run Settigns). There is a section there called "Run Environment", which shows the environment reator uses to run your applicaiton. Make sure your command line is using a similar environment. On windows the PATH variable is usually the most critical.

  • Thanks for the replies,

    Please suggest me to set the 'PATH and the variables'.

    Is there any specific variable which I need to create?
    I saw a similar kind of example on the internet, but don't know how practically I will do it?

    Well thanks again, I will try your suggestions . :)

  • How are you running your application ??

    By clicking the executable ?? Or from inside the SDK-> creator -> run itself?

  • As Tobias wrote PATH is most important. You can set it to bin directory in Qt installation directory (where all dlls sit). Ex. If you install Qt to c:\qt\4.8.2 then add c:\qt\4.8.2\bin to path.
    How to do that? Check "this":

  • @Tobias and Rahul, I am running the programs from IDE(QT creator) by clicking the run and debug buttons(Working) but when I run the programs from the debug or release folder executable all go in vein.

    @Tobias,I have not tried it from command prompt, however I tried your suggestion and the environment is set to 'build environment'.

    @sidewinder, I have installed the QT SDK and below are the PATHs I have tried to set in the path variable, nothing worked (Suggest If I got it wrong and things are not like this):


    Please tell me if this is not the way to solve the issue:
    What have I missed ? Is there something wrong with my installation ? It is all set to the default locations and I haven't changed anything.

    Thanks for your efforts :)

  • bq. C:\QtSDK\Desktop\Qt\4.8.1\msvc2010\bin;

    This one should work. Have you logout -> login after setting PATH? Restarting explorer process should also work. To be certain - reboot :).

  • So, what i understand is, Your application is working form within the SDK. But your executable is not finding the dlls when you try to run .

    If it is so, you might want to go through the" deployment documentation. ":

    You might need to keep qtcore4.dll,qtgui4.dll in the folder folder where exe resides or set the library path in code.

    Or you can set the PATH variable to the Qt - dll folder.

  • Hey sidewinder and Rahul both suggestion worked.

    Thanks a lot :)

  • You're welcome :)

    Please edit the post-title as "Solved" :)

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