EV-Domino: How to finde Notes stub from mail file

Hi folks,

one of our customers has an issue with importing NSF-files properly.

I found that this article applies:

NSF Migrator fails migrate some or many items.
http://www.symantec.com/docs/TECH172116

It sais "2) Delete the corresponding Notes stub from the mail file."

I don't know how to identify the corresponding notes stubs. Does anyone know how to find them?

Thanks in advance!