I asked my vendor to set up a secure FTP solution for us. We use Office365 and Azure. They started off great but then started having issues with the software they are using. THen I got the email below ...

Sftp doesn't use ssl certs like ftps (unless there is some proprietary addition to the sftp server)<BR><BR>Maybe you mean an ssh public key? WinSCP looks to support them as well as all the other ...