When you are in DW and you are applying the upload file server behavior what version of DFP do you have installed? Do you have this installed along with the latest Universal Email? If so this could be the problem. You should not have both of these installed at the same time. You should completely remove any previous versions of DFP that you have installed before installing the new UE4.
Upload file server behaviors that were written with an older version will have this message next to them in the sever behaviors area.