• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 2531
  • Last Modified:

[Qt + MySql] Deploying an Application... Driver not load on other computer

Hi everybody,

I created an application that use a mysql , it work very well at home where qt and the driver are install.

When I try my application on any others computer i got the error message "Drivers not load".

All the DLL are in places, it seems I need to add something to attach the drivers to my application.

Help me plzz !!
  • 5
  • 3
1 Solution
Hello tinzaker,

try to register the drivers on the "away from home" machine
from start menu/run

regsvr32.exe "path to the drivers" (with the " if you have spaces in the path)
ex: regsvr32.exe "c:\my app\my project\needed_dll.dll"


tinzakerAuthor Commented:
I tried : regsvr32.exe C:\Documents and Settings\Alexis\Bureau\File\Programation\C++\Projet\SE\release\QtSql4.dll

but i got this message error : LoadLibrary("Path to dll") has failed, the specified module could not be found.

I don't really know where is the driver of mysql... but i know that i need the QtSql4.dll
It is for mysql uses.
tinzakerAuthor Commented:
oups i forgot the "

but i still have this error : (path to dll) was loaded but the entry point DLLregisterserver cannot be found
The new generation of project management tools

With monday.com’s project management tool, you can see what everyone on your team is working in a single glance. Its intuitive dashboards are customizable, so you can create systems that work for you.


Some things come to mind
- the application is looking for that .dll in a specific place
- the .dll is registered more then once in registry
- this .dll is dependent of another .dll  (use dependency walker to find out if that's the case - http://www.dependencywalker.com/) (I'm thinking of QtGui4.dll, QtCore4.dll QtXm14.dll, mingwm10.dll, qsqlite4.dll, etc)
- according to http://support.microsoft.com/kb/249873 the "Dllname may not be exported, or a corrupted version of Dllname may be in memory. Consider using Pview to detect the file and remove it. ". Or a different version of the .dll is in memory (pview can be found here http://www.teamcti.com/pview/prcview.htm. You'll be able to view the .dlls in memory by going to view menu and choosing module usage. Left click on the .dll and choose Filter Process List to see what's using that dll)
- go to Control Pannel / Administrative Tools and start "Data Sources (ODBC)". Enable tracing. See if in the logs there is some aditional info about the error
- download the MDAC checker to see if no ODBC driver is corrupt (http://www.microsoft.com/downloads/details.aspx?familyid=8f0a8df6-4a21-4b43-bf53-14332ef092c9&displaylang=en)

tinzakerAuthor Commented:
If I look with dependency walker everything is in my project folder on every computer

but when I look out my program with pview, on my computer there some dll that are loaded in the Qt folder.

If I'm not working on my computer, the dll that were in the qt folder are not even mention... I think it's these dll that my program need, but how to attach them to it.

what are ODBC driver... I think I have a link with Visuall...

my compiler is mingw by the way
Unfortunately I do not have experience with mingw
Try to put in the folder (on other computer) all the dlls that are missing from the QT folder
register then with regsvr32

About the ODBC -> http://en.wikipedia.org/wiki/Odbchttp://en.wikipedia.org/wiki/Odbc

tinzakerAuthor Commented:
Thanks man for your help, Ifinally solved my problem after a few day of hard work !!

It's just that you need to specified to your application where you put the driver.

I created a folder named plugins, and add to it the containt of qt plugins folder

The Pview really help me and this web page too, http://doc.trolltech.com/4.1/deployment-windows.html#creating-the-application-package

You just need to go on Pview chack all the dll that are not in the project folder and them.
You have no had this function with the pash of your plugins: QCoreApplication::addLibraryPath("./plugins")

If you have any question just ask me by this post ! or alexj13@videotron.ca

tinzakerAuthor Commented:
I put you good mark because you answered fast !! and I found a perfect clean solution because of you

Thanks man !!!!

You really Helped me
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Featured Post

Never miss a deadline with monday.com

The revolutionary project management tool is here!   Plan visually with a single glance and make sure your projects get done.

  • 5
  • 3
Tackle projects and never again get stuck behind a technical roadblock.
Join Now