This error means that the element could not be found. There was an error with the Document ID that Validator used to try to open the document.
Reported errors can include the following:
The following is an example:
In addition to the information common to all reports, the Document/Note Was Not Found report shows the following:
The field on the document where the link was found.
The type of link (for example, DocLink or URL).
How the link was stored (for example, standard, computed or special).
Type of NoteLink (For example, Named Element, DocLink or Anchor Link).
Text near the error, provided as a hint.