Usage in 64-bit environments
Because the /n software QuickBooks Integrator communicates directly with Quickbooks and Quickbooks does not currently have native 64-bit support, applications that communicate with Quickbooks must be run in 32-bit mode when running on a 64-bit architecture.
On 64-bit machines, you will either need to use the QBConnector.exe provided with the installation to bridge the connection to Quickbooks via a 32-bit application, or you will need to target the X86 processor when compiling your application to create a 32-bit application.