The following appears on a single row in the Load File Discovery Error report for any item encountering the issue:
NONFATAL_ERROR
INVALID_FILENAME
File name does not exist for document

This is caused by eDiscovery Platform (eDP) not recognizing whether a given row in the load file represents an email or a loose file.
1. Select the Case > Processing > Sources & Pre-Processing > Manage Sources > load file source.

2. Select Identifiers
3. Set 'Email identifier' so it uses a value of 'To' and then check the 'Any value' box.

4. Select File Types
5. Put a check in 'My load file contains loose files and/or attachments'.
6. Set the 'File Name' value to the appropriate File Name field.
7. Set the 'File Extension' value to the appropriate File Extension field.

8. Click Save.
NOTE: Support cannot modify load files. If the load file does not contain fields for emails (IE To, From) or fields for loose files (IE FileName, FileExtension) then please obtain a load file that does contain these fields.