Upload to dropbox doesn’t work

Hello,

I’m just trying BackWPup on one big site and if the backup process works fine (no error, no warning), it doesn’t upload the files to dropbox. I’ve tried twice, with my sysadmin monitoring our dedicated server to see if specific resources settings were needed (Pmemory, timeout, etc.).

BackWPup dashboard at the end of the backup: http://i.imgur.com/8rLmwbi.jpg
BackWPup dropbox folder 8 hours after the end of the backup: http://i.imgur.com/GEQu23S.jpg
The 2 folders that BackWPup added in our server: http://i.imgur.com/kW0OMmn.jpg
The content of the 2nd one: http://i.imgur.com/8rLmwbi.jpg
The proof that dropbox is properly associated to the site: http://i.imgur.com/A1pwBK1.jpg

Thanks in advance for your help.

Best regards,
Franck.