Q: iTunes not backing up?

Now, this is a question asked and I believed answered before, but I'm on Windows and not a Mac so it's no use to me. Using iTunes (latest versions and all) I've always been able to backup my devices no problem. But now if I click backup nothing happens and the 'ding' sound for completion plays, but there is no backup made or anything. It even says in iTunes itself that it can't find any backups, as well as non-iTunes software. This happens on my iPad Mini 2 and iPod Touch 5g.