Cant Upload Files Properly

SmartFTP will act like it is loading the files. It will ask me if I want to over wright a file. It will (sometimes) even show the status of the upload. However, when the transfer is complete, the files cannot be found (I get a 404 error). I forwarded port 21 on my modem and my router, but still have not been able to upload any files.

Thanks for any help.