I was once training a tech support class for a group of people soon to be working in a call centre taking helpdesk support. This was fine until one candidate put their hand up, and the conversation followed as such :
Candidate : My mouse is broken.
Me : Let me have a look for you (I then walked over to her workstation)
Candidate : No no its not the mouse, its my table, my table is broken.
Me : How so?
Candidate : Cos it isnt long enough and when I scroll down, I run out of table, can I get a longer table?
Me : Aha, I think I have found your problem, when you get to the bottom of the table just pick up your mouse and place it at the top of the table, then scroll down again...
Candidate : Wow, thats clever, I have been stuck for ages thinking it was broken.