EGL0203E `The function_name String function failed with error code 20.`

Explanation

The index of a DBCHAR or UNICODE substring must be odd so that the index identifies the first byte of a character.

User Response

Do as follows:

Change the program logic to ensure that the index arguments passed to the function are valid; or
Call the function in a try statement, or set vgVar.handlesysLibraryErrors to 1 before calling the function, so that the program can handle the error.