Can I export directly to a USB from Elements 15?

Can I export directly to a USB from Elements 15?

I tried exporting a project yesterday from Elements 15 using my partners MacBook Air (OS X El Capitan 10.11.6). Because there is not enough space on The Mac I exported via the device settings, on HD 1920x1080 and chose my USB stick as the destination. However, once the export finished, it did not export the video properly? It came up as a MOV. file but wasn't unplayable and only 24 bytes, when it was a 45min video that should be around 5GB. The USB has more than enough free space on it! Am I doing anything wrong? Would I be able to export and save to an external hard drive instead? Or does it have to be saved to the Mac or Laptop itself? And help would be really appreciated.