In the DayliteDocs preferences in the Docs2Daylite section this option is available is you chose to Save file attachment as a reference to a file.
Instead of creating a reference in the local location (for example, on your desktop), the file is copied to the alternate path (for example, a shared folder on a file server) and a reference to that file is stored in Daylite.
If other Daylite users should also have access to the document, make sure that they also have access to the location.
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