Most encodings have limitations that determine what type of text it can represent. For example, some are numeric-only and some require text of a specific length.

If the value of the Text property cannot be represented using the current CodeType, then the error message will be shown in the control.

In this case, the EncodingException property returns details about the exception that prevented the bar code from being generated.

Reference

C1BarCode Class
C1BarCode Members