Such interactive prompts should only be displayed for interactive sessions (such that have TTY). WinSCP do not have TTY. Recommend your IT people not to display the prompt for SSH session without TTY.

Or use SFTP instead of SCP.

Hi , I was using winscp successfully on one server when the IT people upgraded the local ssh package and defined banner prompt interactive , where once logged on the system , you have to acknowledge a question by 'y' (are you sure you undesrtood the security statement etc...) and then , press enter .
Question is : is it possible to define this sequence within WinSCP for me to be able to still use it ?

Thanks,
JSG