One of my ftp clients got kind of angry at me for who knows what reason a while ago (temporarily only), so I found an alternative means of uploading my content (to rule out a problem with my program). I ended up blaming the program. So, I dunno, try restarting your computer? I use Filezilla so I know firsthand it can decide to just quit sometimes. It says it's doing it's thing but I no longer believe it sometimes. (Sometimes I would just entirely delete the file to replace it and it wouldn't actually even go away.)
I will now tip my hat in recommendation to check out
codeanywhere.com because it's become my new favorite way to make changes to my live site rather than reuploading files. I just change a single line and press 'save'. It's like an IDE but in the browser.
And happy new year!
