FTP SSL/TLS Implicit encryptions, more ports then 990?

hi.

Im behind a very strict firewall and have opened up 990 to be able to connect to a host FTP server.

I can connect (the host server sees that I am connected) but I get a error that I cant list folders.
When trying to upload a file I get an error

So, my question is this:
Does WINSCP use one port to connect to the server , and another for actual data transfer?
If so, is it a random port or can it be locked down to say 991?

Thanks

I should ofcourse include the error i got when trying to upload a file :oops:

"Copy files to remote side failed, cant open data connection".

With FTP protocol the server connects back to client for data transfers. Try switching to passive more to circumvent that.