Uploads stopping...reason unknown?

Hi guys, been using Smart FTP for as long as i can remember...however recently i'm getting really odd errors nearly exactly the same time on whatever file the transfer fails and doesn't complete, the log of the most recent one is shown below, by the 'software' i guess it means smartftp? as i can't see what else it can be.




227 Entering Passive Mode (99,999,99,99,999,99).
Opening data connection to 99,999,99,99,999 Port: 99999
LIST -aL
150 Opening ASCII mode data connection for file list
765 bytes transferred. (12.0 KB/s) (62 ms)
226 Transfer complete.
Remote file exist check: 'xxxxxxxxxxxxxxxxxxxxxxxxx'.
SIZE xxxxxxxxx.wmv
213 27702202
MDTM xxxxxxxxxxx.wmv
213 20060713004248
TYPE I
200 Type set to I
PASV
227 Entering Passive Mode (99,999,99,99,999).
Opening data connection to 99,999,99,99,999 Port: 99999
STOR xxxxxxxxxxx.wmv
150 Opening BINARY mode data connection for xxxxxxxxxxxx.wmv
An established connection was aborted by the software in your host machine.
Server closed connection
Transfer failed.










Cheers in advance for any help you can provide, i hope its not something really noobish but i guess it probably will be.

Your server (host machie) aborted the data connection. Use the Transfer Queue for all your transfers.

Regards,
SmartFTP