Did you check if that path to your editor is still valid? Maybe you have uninstalled the editor? Or maybe it got reinstalled to another location.

You can configure a new path or new editor in preferences:
https://winscp.net/eng/docs/ui_pref_editor

Hi, I have been using WinSCP successfully for about a year but recently got this error (attached) while trying to open a file within the system. I have tried refreshing the system, resynching, reloading, anything that would reestablish the connection but I keep getting the same error. Does anyone have a solution to this issue?