My Job is Annoying

I work at a IT help-desk in the health care industry. We take calls for a few different hospitals helping the nurses and doctors with computer issues. The most common issue is locked AD account and incorrect passwords. I had a doctor call me today and argued with me about how the system is flawed because he keeps getting an invalid password entered error. Why is it so hard for people to just admit that they made a mistakes and just let you help them? Now this "Doctor" goes on a tangent about how the system is down and there is a problem with the application because he is for sure his password is correct. So what I do is remote into the doctors computer and had him type the username and password again only to verify that the freaking! CAPS LOCK was on. SO I kindly tell him to turn off the caps lock and sign in again; I hear in the background that he is logging into the windows desktop; so I ask if everything is OK and he just hangs up in my face. I want to know if there are any others out there who have to deal with idiots like this on there jobs. Put a story on the blog.