Hi!
Have you compiled your application as x86?
This is necessary for the VIX-API to work on 64bit systems, because the VixCOM.dll is a 32bit library and will only be emulated by the WoW64 layer if the application is compiled as x86.
To compile your application as x86, in Visual Studio go to the application properties page, select the Build tab and select "Platform target: x86".
Best regards,
Alex