Diagnosis
A BDOC field - not coming from the root segment - is used for themapping of an extract field that can be selected by BW. And noSelection module is specified in transaction BWA1.
Without specification of a Selection module a generic module will becreated. But this module is not able to handle other conditions thanthose refering to fields of the BDOC root segment. This will cause anruntime error during the extraction.

Procedure

• You can either hide this field of the extract structure from BW
by entering an 'A' in row Selection of tab stripExtract structure of transaction BWA1. But normally youneed this field, otherwise you would not have mapped BDOC informationin it.

• Or you change the mapping. Doing so, you can only use fields
from the BDOC root segment.

• Or you specify your own Selection module that overcomes the
restriction of our generated module.