I'm having an issue with hiding the interface for a device. I'm invoking aquire when no paper is loaded into the scanner(ADF) and the device pops up a dialog stating there is no paper loaded. This dialog popping up is fine but it seems as though the error is being buried by the DotTwain API. There is no exception being thrown or Canceled/Finished event being fired in code to notify me to close the async connection to the device. I'm not sure if this is a problem being caused by the driver not functioning correctly, but this is happening on both a Panosonic 2065 and a Xerox DocuMate 152. Is there a way to detect if the ADF is loaded or not before I make the call to Aquire?

You can check the Device.DocumentFeeder.Loaded property to see if there are pages loaded (assuming the scanner supports this feature).

If you enable tracing for DotTwain (http://www.atalasoft.com/KB/article.aspx?id=10027), it will show us what the driver is returning when no documents are loaded.  Once you close the driver dialog, you should at least get an AcquireFinished event.