Below is a list of things that you can try adjusting to improve invoice identification and interpretation. The items in the list are some of the many ways of improving system performance.
If Interpret has problems capturing a field, improving the format specification can greatly improve interpretation and field capture. If a field has a well-defined format that is the same on all invoices (or on all invoices from a single supplier), define the format specification precisely.
Whenever possible, avoid using X to specify a character position. X means that the character can be either a letter or a number, and this uncertainty can hinder interpretation. If it is always one or the other, use A or N instead of X. (See Format specification for fields and identifiers.)
Use active validation whenever possible.
Ensure that the character set of the language you are interpreting contains any non-alphanumeric characters (such as parentheses) that are to be interpreted. (Instructions.)
Adjust Eiglobalextra.ini, for example by adding customized field types or adjusting the business logic.
Whatever the source of the invoices, you want to be sure you are working with the best images you can create with your equipment.
Experiment with contrast.
Experiment with Kofax or ISIS settings. For example, try deactivating the INVOICES deskewing by setting the SoftwareDeskew setting in Eilocal.ini to 0 and using Kofax or ISIS deskewing, instead.
If your scanner has an image processing card, use it. See Scanner settings and filtering operations.
If you are scanning color or grayscale invoices, two things that can improve interpretation are adjusting conversion of the image to black and white and using a color filter.