You can eliminate that by helping us fix the bug.

I have sent you an email with a debug version of WinSCP to the address you have used to register on this forum.

Apparently getting an error number and a technically grammer-incorrect message on exceptions is not friendly. I jokingly suggested perhaps it should show a frowny face like common chiche programs do nowadays, and they agreed it would be better. Somehow.

So this is my feature request, since I promised them I would make one for this exact issue, which is: Eliminate the "scary a$s error windows when I shut off the server it was connected to", i.e. the ones that read as follows: