dataport - illegal characters

Hello - hoping someone might have some ideas about an issue we are experiencing with DataPort.

When importing documents some are throwing the error:

Error retreiving the next object. Reasons to follow: ID: XX Uri: 0 Details: Illegal characters in path

We can't seem to find the illegal characters preventing the import however when we drag and drop it manually into HPECM it has no issues.

Any ideas? Thanks in advance.