In the Docbox Print Driver, normal processing will move the PDF to the watch folder prior to passing it to Docbox server.
The watch folder is located at C:\Users\userid\AppData\Roaming\DMSPD\Watch.
It is possible to redirect PDFs to a different location by modifying the config file, DMSPost.exe.config.
Change WatchDirectoryOverride to point to the required folder. This location will need to be accessible by all users of the Print Driver.
Example: