Support call with client on a company-wide web-based application some years ago.
Client: I can't log in to the application - it doesn't work!
Me: Are you entering the correct password?
Client: There's nowhere for me to enter my password. Just a Username box.
Me: Wait... You can't see a password box? Can you describe exactly what you do see? (I know full well it has to be there, as hundreds of other users can get in).
Client: In the middle of the screen is the company logo, and at the bottom of the page is a username box, and nothing else.
Me: Look to the right of the screen. Do you see a scroll bar?
Me: Can you scroll downwards?
Client: The password box has appeared now. Bye.