Well, if you know a bit more about sync, there are different types of it(One way, two way, 'echo only' etc.). Sure, I failed to understand all of how Dropbox wo

Well, if you know a bit more about sync, there are different types of it(One way, two way, 'echo only' etc.). Sure, I failed to understand all of how Dropbox worked (and that's why lost my files), but probably the previous sync software like SyncToy from MS had pampered me. Have you ever done contacts syncing on phones? If you look properly, it will give you all different options for syncing. Many sync software are extremely cautious about deleting multiple files on the server, and that is what I was expecting from Dropbox too.