Hi everyone, I hadn't found a anwser on the web, so i ask to you. I am unable to run my compiled mysql driver on a deployment solution. On the pc A the app work fine when run with QtCreator, but via the .exe in the following working directory, the driver is not loaded : root/ -----/bin --------/app.exe --------/libgcc_s_dw2-1.dll --------/mingwm10.dll --------/QtCore4.dll --------/QtGui4.dll --------/QtSql4.dll -----/sqldrivers --------/libmysql.dll --------/qsqlmysql4.dll Whereas with libmysql.dll under bin/ driver is loaded. Now on the pc B, with no Qt or MySQL lib installation and with any of the 2 last working dir, the driver is not loaded. pc A : Qt 4.7 2010.05, Win 7 pc B : Win 7 Thanks for your help !