The related article import allows you to record relationships between articles. The is a different import than the article import. It is only possible to use articles that are known in the database. With this error message a non-existing article is linked or an expired article is linked.
Solution:
Find the expired articles listed in the RelatedArticleNumber column and change their availability or remove them from the import file.
Find the unknown articles in the RelatedArticleNumber column and enter them into the database or delete them from the import file.
