If receiving a file not found error message during a migration, referencing a file that was successfully added to the job when the job was created, the issue is most like a bad file name. (A name with spaces or special characters in the name)
When adding files (sqrs, dms, ..etc) during the creation of a job, the Change workstation maybe using Windows protocols to find the actual file.
But during the migration task, the system is processing command line functions related to the specific PeopleSoft environment and may now be utilizing Unix protocols.
For example, if the file name has a space in its name (Migration_670 vendor.dms), windows will add the file to the job properly.
But when it comes time to process the dms file, DataMover, under Unix can not find the file Migration_670, as the name is truncated at the space.
To avoid, or correct, this issue ensure that the file names are valid for all appropriate operating system conventions.