I think I wasn't very clear. Sorry. Since there was a temporary issue when transferring that particular backup you have ended up in a situation where non-sequentially numbered archive parts are left behind on your server. This means that the Transfer Archives from Manage Backups will always fail. The reason is that after transferring the first part it will try to transfer the second part. If the file for the second part does not exist the upload is considered failed and it stops dead on its tracks.
The only thing you can do about this particular backup is download the remaining parts through FTP / SFTP and then manually upload them to Dropbox, together with the other, already uploaded, part files.
Nicholas K. Dionysopoulos
Lead Developer and Director
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