Help WS FTP 12 keeps jamming

I have used WS_FTP LE 6 for ages and found it 100% reliable.

I just downloaded version 12 and its a good looking program... but... it keeps locking up when uploading files. It uploads 3 or 4 files then sticks. Sometimes it says the remote server blocked me, sometimes it says socket error.

I can upload, but I have to do one file at a time. But my site has 2800 files (not funny!)

I am searching for an old version 6 to download, but not found one yet.

Anyone got any ideas whats happening???

cheers all. Jack.