What is the meaning of the error message "Min length of 1 undershoot." that appears, when an external SEPA file is sent?
This error message means that a tag without content is used in the SEPA file. This is not allowed. If there is no content, then the tag should not appear at all, e.g. for the unstructured remittance information, a tag of the kind
<Ustrd> < /Ustrd>
is not allowed.