Diagnosing and Reporting DTWAIN Problems

In some cases, a TWAIN device either fails to acquire the image, or some other error occurs that prevents the images from being acquired.  If problems persists, the first line of defense is to try the DTWDEMO.EXE testbed application, and see if the DTWDEMO program operates correctly.  If it does operate correctly, then this indicates that you're doing something incorrect in your program.

The next line of defense it to make sure that you check the return values of the DTWAIN functions that return errors, and usage of the DTWAIN_GetLastError function to see exactly what the last error was that occurred.

The next thing that can be done is to generate a TWAIN log.  To do this, the DTWAIN_SetTwainLog file using the DTWAIN_LOG_ALL flag and specifying a filename to log to can be used to generate a log, or at runtime, you can turn the logging on or off using the DTWAIN32.INI settings.  The logs will give much more low-level, detailed information as to what DTWAIN and your TWAIN device is doing during the acquisition process.  The information contained in the log may be a little overwhelming, but it contains a wealth of information that can root out problems with either the way DTWAIN is operating, or how your TWAIN device is operating when asked to acquire an image or set of images.

If DTWAIN_LOG_ALL is used, all errors are reported, and you may get benign error messages when generating the log.  You can safely ignore these message boxes.

Before reporting any problems to the DTWAIN technical support team, make sure that you have tried the DTWDEMO.EXE program to make sure your device is working properly, and that you have generated a TWAIN log.  With the log file, you have a diagnostic log for the tech support team to study and give reasons and solutions to the problem.

To report errors or problems with DTWAIN, please contact support@dynarithmic.com and have available log files.