How to get rid of the error: “Data source name not found and no default driver specified” in .net?

Question

I was trying to built a asp.net web app with the connection string defined in the webconfig file. When I try to debug I am getting the following exception:

ERROR [IM002] [Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified

The connection string looks like this:

connectionString="Driver={MySQL ODBC 5.1 Driver};server=XX.XX.XX.XX;port=3306;database=db_name;user=username;pwd=pass;option=3;" providerName="System.Data.Odbc"/>

The driver is installed and I can see it listed in the 'ODBC Data Source Administrator'.

I tried changing the build configuration to 'Any CPU', still it failed.

Can somebody help me out to figure whats going on here??

Thanks,

Uday

Answer 1

If you have installed the x64 version of the ODBC driver you can use it compiling the executable as default (both CPU) otherwise you have to compile the executable as x86 only and use the x86-32 driver.

Keep in mind that by default on x64 os an application compiled as both CPU (x64 and x86) will use the 64bit version of the driver, this means that if you install the 32bit version of the ODBC driver and compile the executable as Both CPU or x64 you will get the error, so you have to compile the application only x86.

Answer 2

You could configure VS to use IIS instead of the internal one, plus you would get more experience configuring IIS correctly for your web app (ie Windows Server 2k8 R2 has pretty drastic configuration/security differences than previous versions). If you configure your AppPool to run under 64 bit then your code should also run in 64 bit mode.