hi David, im not the best person to get a response from but i should do.
if you plug your phone in with a USB cable, go onto your phone change the setting that your phone can receive/send files of a certain kind that will be in the bar up top (slide down) just click that to get to the settings. then make sure you transfer into the correct files, if your connection is faulty you may have problems...
the other alternative is using bluetooth, pair your 2 devices and click the mobile devices name on the computer click "send files" and there you can chose the files you need to send.
thank you and i hope this helps
-Lachie