I have had the same problem with Fotolia, Canstock and 123RF. Always at the weekend - perhaps that is the problem. I use Filezilla and have for some years - but could not connect to Canstock last week for days. I had some uploaded, but they were all thumbs and refused. Thumbnails are not on my computer, as they are with my records on an external hard drive. It is annoying as the deletes count against my statistics! Same with other files which did not upload fully - sometimes less than half the image was displayed.