Unhandled error: C:/QB_FILE/Company.QBW: Could not start QuickBooks.:

HRESULT = -2147220472 (FFFFFFFF80040408) in BeginSession on C:/QBFILES/Company.QBW

Source: QBXMLRP2.RequestProcessor.1,

Last DLL Error: 2

The latest QuickBooks SDK does not allow you to run the QuickBooks communications DLL in debug mode.  As a result, we separated all QuickBooks communications functions into their own DLL, then set that to Release mode in Visual Studio, while keeping all other modules in Debug mode.

The isolated QB communications allowed us to fully debug our logic.

If you have further questions, please down hesitate to ask.