I had minor issues while using FileZilla. This came down to too many simultaneous connections. Perhaps this is also causing your troubles.
Try setting it to 1 connection and transfer max.
Other things to check
- Did you use the right port? (it is not default FTP port 21)
- Internal firewall, not sure what kind of network set-up you have going, but see above, since it is not a web-standard port, there could be firewall rules denying access, have you checked that?
- Use passive transfer instead of active
- 1 simultaneous transfer / connection open.
Comments
Try setting it to 1 connection and transfer max.
Other things to check
- Did you use the right port? (it is not default FTP port 21)
- Internal firewall, not sure what kind of network set-up you have going, but see above, since it is not a web-standard port, there could be firewall rules denying access, have you checked that?
- Use passive transfer instead of active
- 1 simultaneous transfer / connection open.
Good luck!